Support for size of gravatar image

Added support for the size (s) argument in the Gravatar API
Replace a substring using regex.
Merge pull request #15 from gmist/re_username

Replace a substring using regex
Optimized signin.less
Updated sign-in buttons to the latest version
Updated Font Awesome to 4.0.1
Update modelx.py
Update modelx.py

this breaks compatibility
Update UserX, with back compatibility
Update user_list.html
Update profile.html
Merge branch 'patch-1' of github.com:xcash/gae-init
Fixed avatar for HDPI screens in user_list.html
Updated Bootstrap to 3.0.1
Update util.py
Update admin.py
Update main.py
Merge pull request #18 from topless/patch-1

Added email_filter for email form fields
Form macros are now accepting keyword arguments for stuff like autofocus, placeholder, etc
Autofocus flag is now set to the first input in forms