[Fix bug 740990] Allow plus sign in skills
Fix bug 948041 - "Is basket working?" management command

New command is "manage.py check_basket"
[fix bug 969039] Change moderated group's join notification.
Merge pull request #793 from caktus/740990-plus-sign-in-skills

[Fix bug 740990] Allow plus sign in skills
Merge pull request #841 from glogiotatidis/916800

[bug 916800] Register auth.Group to Admin Panel.
[fix bug 970806] Switch to users.UserProfile instead auth.User in Admin Panel.

Since all of our models that relate to users link to UserProfile, make
the later the entry point for user profile edit in Admin Panel. This
allows us to inline models like GroupMembership which couldn't be
inlined within User.
[fix bug 974011] Fix logout button in Admin Panel.

Because we're using BrowserID we need to redirect users our custom
logout view to properly sign them website and delete the BrowserID
session.

At the same time this fix solves the 500 error that was raised when a
user clicked the logout button from the admin panel, which was due to
'registration' app not being excluded from Jingo.
Merge pull request #840 from glogiotatidis/974011

[fix bug 974011] Fix logout button in Admin Panel.
[Fix bug 969116] Updated email sender and signature.
Merge pull request #842 from glogiotatidis/admin-userprofile

[fix bug 970806] Switch to users.UserProfile instead auth.User in Admin Panel.
Merge pull request #839 from venksv/b_969116

Fixed bug 969116 - Update email sender and team signature for email noti...
[docs] Add PIL/freetype note for Mac OS X
[fix bug 971969] Fix criteria error message and required indicator.
Merge pull request #847 from glogiotatidis/971969_3

[fix bug 971969] Fix criteria error message and required indicator.
[fix bug 973387] Allow curators to change accepting_new_members field.
Merge pull request #766 from caktus/948041-is-basket-working

Fix bug 948041 - "Is basket working?" management command
[fix bug 979837] Add Mozilla Webmaker to External Accounts
Merge pull request #851 from mishravikas/fix_979837

[fix bug 979837] Add webmaker to External Accounts
[fix bug 930999] Add username_not_url validator to external accounts.

Refactor username_not_url validator

Simplify username validator

Change _lazy to _

Simplify username_not_url
[bug 930999] Add ExternalAccountForm tests.