Change UserFactory to create vouched users by default.

Since the most common test scenario requires vouched users to work, I
switched UserFactory to vouch users by default. Also added parameter
'vouched' to easily explicitly control the vouch status.
Don't need to force ElasticSearch update after UserFactory.create().
Merge pull request #871 from glogiotatidis/testscleanup

Clean up testcases
Cleanup templates.
Merge pull request #900 from glogiotatidis/templates

Cleanup templates.
[fix bug 990538] Beautify and cleanup group urls.
Merge pull request #885 from glogiotatidis/niceurls

[fix bug 990538] Beautify and cleanup group urls.
[Fix bug 703316] Update invite email
Incorporating feedback