Can upload names with utf-8 characters via "Paste Usernames" textbox

When uploading cohorts we support two different ways to do it:
1. Uploading via a file.
2. Uploading via a "paste usernames" textbox.

For the second case we need to support unicode handling of user names as
WTForms works with unicode by default. See:
http://wtforms.readthedocs.org/en/latest/faq.html#does-wtforms-support-unicode

Bug: 64893
Change-Id: Ia327cf328e1b6649b7e6821ef8921539d3e14cf1
Upgrading Alembic

Prior to version 0.6.4 alembic used pyc files to run migrations.
This behaviour was reported as a bug and as of 0.6.4 the flag
sourceless=true needs to be added so alembic uses pyc files.
By default alembic will only use py files.

Bug: 64001
Change-Id: I0bdce8b234300852d539d4bdf2a65b1e14481241
Merge "Can upload names with utf-8 characters via "Paste Usernames" textbox"