1159067 - Read user cred from config

Allow pulp to read user credentials from users admin.conf
if he/she does not want to provide password on command prompt
or --password in pulp-admin
add doc of permissions argument to role update
1128226 - Adjusting 'Repository Content Behavior' section name
1021970 - Add an example how to retrieve permissions for a particular resource.
1004623 - References to old collection names and content_unit_count needs to be updated
1116825 - Adding a non-existent user to a role now returns HTTP 400 instead of 404.
Merge pull request #1310 from jeremycline/1116825

1116825 - Adding a non-existent user to a role now returns HTTP 400 instead of 404.
Merge branch '1066022' into 2.4-release
Merge branch '2.4-testing' into 2.5-testing
Merge branch '2.5-testing' into 2.6-dev
Merge pull request #1337 from CUXIDUMDUM/cuxidumdum/1159067

1159067 - Read user cred from config
Updates to docs to describe bug process
Merge pull request #1338 from beav/bugprocess

Updates to docs to describe bug process
I hit "merge" before pushing an updated commit with feedback from #1338.

This commit has some minor updates to the PR.
Merge pull request #1340 from beav/bugprocess

I hit "merge" before pushing an updated commit with feedback from #1338.
Merge branch 'master' into mongoengine-taskstatus