Fix hg for python3 (#4528)

* Remove import of unused ConfigParser (ConfigParser has been renamed in py3)
* When retrieving version, normalize to a native string

source_control/hg.py

@@ -23,8 +23,6 @@
 # You should have received a copy of the GNU General Public License
 # along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
 
-import ConfigParser
-
 DOCUMENTATION = '''
 ---
 module: hg
@@ -92,6 +90,12 @@ EXAMPLES = '''
 - hg: repo=https://bitbucket.org/user/repo1 dest=/home/user/repo1 revision=stable purge=yes
 '''
 
+import os
+
+# import module snippets
+from ansible.module_utils.basic import AnsibleModule
+from ansible.module_utils._text import to_native
+
 class Hg(object):
 
     def __init__(self, module, dest, repo, revision, hg_path):
@@ -123,7 +127,7 @@ class Hg(object):
         if rc != 0:
             self.module.fail_json(msg=err)
         else:
-            return out.strip('\n')
+            return to_native(out).strip('\n')
 
     def has_local_mods(self):
         now = self.get_revision()
@@ -270,6 +274,5 @@ def main():
         changed = True
     module.exit_json(before=before, after=after, changed=changed, cleaned=cleaned)
 
-# import module snippets
-from ansible.module_utils.basic import *
-main()
+if __name__ == '__main__':
+    main()