Update salt/modules/mongodb.py

Rectification of 'TypeError: port must be an instance of int' if using specified settings for Mongo.
Use outputters in runners/manage.py.
Add a silent outputter.

This allows me to call a runner and only get the return data back.
Moved groups assignment out of useradd to avoid errors when the group is the same as the default user group
check whether a usergroup is set explicitly as part of the groups parameter and set it as default group on systems with usergroups enabled
added try..except around file open call as this will fail on some systems.
In such cases it is assumed usergroups are not enabled.
* some cleanup
* pep8 fix
Added show_diff kwarg to file.managed.

This can be set on a per-file basis so that potentially-sensitive
content can be omitted from logs.
Added -r requirements.txt to dev_requirements.txt.

When calling: `pip -r dev_requirements.txt` the `requirements.txt` file
will automatically be included as well.
fix #4065
fix pep8
Merge pull request #4088 from UtahDave/develop

Add link to 64bit Windows installer
Add error checking to major pieces of apt.py module
Remove trailing whitespace
Check for errors in dpkg.py

Also fix it so that this module will work AT ALL.  cmd.run returns a
dict, which does not support splitlines(), so I think this was
completely broken, and people just don't use it so we didn't know.
Fix pep8 line length
Add more error-checking to apt.py
Fix syntax error (whoops)
Catch the exception for when salt is unable to connect to syslog.
Bring to the developer's attention that a version bump might be missing.