Bring py27-old into line with other test envs

tox.ini

@@ -83,6 +83,17 @@ deps =
     mock
     lxml
     coverage
+
+extras = all
+
+whitelist_externals =
+    sh
+
+setenv =
+    {[base]setenv}
+
+passenv = *
+
 commands =
     /usr/bin/find "{toxinidir}" -name '*.pyc' -delete
     # Make all greater-thans equals so we test the oldest version of our direct
@@ -95,6 +106,9 @@ commands =
 
     {envbindir}/coverage run "{envbindir}/trial"  {env:TRIAL_FLAGS:} {posargs:tests} {env:TOXSUFFIX:}
 
+usedevelop=true
+
+
 [testenv:packaging]
 skip_install=True
 deps =