Add diff for both file contents and file attributes to lineinfile

Using the difflist feature added in ansible/ansible@c337293 we can add
two diffs to the `diff` dict returned as JSON: A `before` and `after` pair of
changed file contents and the diff of the file attributes.

n.b.: the difflist handling from the above commit is logically broken.
PR will follow.

Example output:

    TASK [change line and mode] ************************************************************
    changed: [localhost]
    --- before: /tmp/sshd_config (content)
    +++ after: /tmp/sshd_config (content)
    @@ -65,21 +65,21 @@
     X11DisplayOffset 10
     PrintMotd no
     PrintLastLog yes
     TCPKeepAlive yes
     #UseLogin no

     #MaxStartups 10:30:60
     #Banner /etc/issue.net

     # Allow client to pass locale environment variables
    -AcceptEnv LANG LC_*
    +AcceptEnv        LANG LC_* GF_ENV_*

     Subsystem sftp /usr/lib/openssh/sftp-server

     # Set this to 'yes' to enable PAM authentication, account processing,
     # and session processing. If this is enabled, PAM authentication will
     # be allowed through the ChallengeResponseAuthentication and
     # PasswordAuthentication.  Depending on your PAM configuration,
     # PAM authentication via ChallengeResponseAuthentication may bypass
     # the setting of "PermitRootLogin without-password".
     # If you just want the PAM account and session checks to run without

    --- before: /tmp/sshd_config (file attributes)
    +++ after: /tmp/sshd_config (file attributes)
    @@ -1,3 +1,3 @@
     {
    -    "mode": "0700"
    +    "mode": "0644"
     }

lib/ansible/modules/files/lineinfile.py

@@ -166,10 +166,10 @@ def write_changes(module,lines,dest):
     if valid:
         module.atomic_move(tmpfile, os.path.realpath(dest))
 
-def check_file_attrs(module, changed, message):
+def check_file_attrs(module, changed, message, diff):
 
     file_args = module.load_file_common_arguments(module.params)
-    if module.set_fs_attributes_if_different(file_args, False):
+    if module.set_fs_attributes_if_different(file_args, False, diff=diff):
 
         if changed:
             message += " and "
@@ -182,6 +182,11 @@ def check_file_attrs(module, changed, message):
 def present(module, dest, regexp, line, insertafter, insertbefore, create,
             backup, backrefs):
 
+    diff = {'before': '',
+            'after': '',
+            'before_header': '%s (content)' % dest,
+            'after_header': '%s (content)' % dest}
+
     if not os.path.exists(dest):
         if not create:
             module.fail_json(rc=257, msg='Destination %s does not exist !' % dest)
@@ -194,7 +199,8 @@ def present(module, dest, regexp, line, insertafter, insertbefore, create,
         lines = f.readlines()
         f.close()
 
-    msg = ""
+    if module._diff:
+        diff['before'] = ''.join(lines)
 
     if regexp is not None:
         mre = re.compile(regexp)
@@ -270,6 +276,9 @@ def present(module, dest, regexp, line, insertafter, insertbefore, create,
         msg = 'line added'
         changed = True
 
+    if module._diff:
+        diff['after'] = ''.join(lines)
+
     backupdest = ""
     if changed and not module.check_mode:
         if backup and os.path.exists(dest):
@@ -277,10 +286,16 @@ def present(module, dest, regexp, line, insertafter, insertbefore, create,
         write_changes(module, lines, dest)
 
     if module.check_mode and not os.path.exists(dest):
-        module.exit_json(changed=changed, msg=msg, backup=backupdest)
+        module.exit_json(changed=changed, msg=msg, backup=backupdest, diff=diff)
 
-    msg, changed = check_file_attrs(module, changed, msg)
-    module.exit_json(changed=changed, msg=msg, backup=backupdest)
+    attr_diff = {}
+    msg, changed = check_file_attrs(module, changed, msg, attr_diff)
+
+    attr_diff['before_header'] = '%s (file attributes)' % dest
+    attr_diff['after_header'] = '%s (file attributes)' % dest
+
+    difflist = [diff, attr_diff]
+    module.exit_json(changed=changed, msg=msg, backup=backupdest, diff=difflist)
 
 
 def absent(module, dest, regexp, line, backup):
@@ -288,11 +303,19 @@ def absent(module, dest, regexp, line, backup):
     if not os.path.exists(dest):
         module.exit_json(changed=False, msg="file not present")
 
-    msg = ""
+    msg = ''
+    diff = {'before': '',
+            'after': '',
+            'before_header': '%s (content)' % dest,
+            'after_header': '%s (content)' % dest}
 
     f = open(dest, 'rb')
     lines = f.readlines()
     f.close()
+
+    if module._diff:
+        diff['before'] = ''.join(lines)
+
     if regexp is not None:
         cre = re.compile(regexp)
     found = []
@@ -308,6 +331,10 @@ def absent(module, dest, regexp, line, backup):
 
     lines = filter(matcher, lines)
     changed = len(found) > 0
+
+    if module._diff:
+        diff['after'] = ''.join(lines)
+
     backupdest = ""
     if changed and not module.check_mode:
         if backup:
@@ -317,8 +344,15 @@ def absent(module, dest, regexp, line, backup):
     if changed:
         msg = "%s line(s) removed" % len(found)
 
-    msg, changed = check_file_attrs(module, changed, msg)
-    module.exit_json(changed=changed, found=len(found), msg=msg, backup=backupdest)
+    attr_diff = {}
+    msg, changed = check_file_attrs(module, changed, msg, attr_diff)
+
+    attr_diff['before_header'] = '%s (file attributes)' % dest
+    attr_diff['after_header'] = '%s (file attributes)' % dest
+
+    difflist = [diff, attr_diff]
+
+    module.exit_json(changed=changed, found=len(found), msg=msg, backup=backupdest, diff=difflist)
 
 
 def main():