[fix bug 842293] Allow filtering of incomplete profiles in Admin panel.
[fix bug 809481] Do not use hash when username is taken.
[fix bug 842292] Handle incomplete profiles.

Don't index in ES incomplete profiles.
Don't list incomplete profiles in groups.
Don't show profile of incomplete profiles.
[fix bug 827514] Allow sorting users based on country, voucher and is_vouched.
[fix bug 844057] Remove duplicate error message.
[fix bug 844067] Set email field in Invite page to autocomplete=off.
[fix bug 844093] Don't expose invited user emails.
Merge pull request #413 from glogiotatidis/invite

Invite fixes
Merge pull request #408 from glogiotatidis/incomplete-profiles

Incomplete profiles
Merge pull request #412 from glogiotatidis/827514

[fix bug 827514] Allow sorting users based on country, voucher and is_vouched.
[fix bug 843583] Do not list non-vouched users in search or groups by default.
Merge pull request #411 from glogiotatidis/843583

[fix bug 843583] Do not list non-vouched users in search or groups by default.
[fix bug 845257] Fix query for common skills in Functional Area.
Merge pull request #414 from glogiotatidis/845257
Fix typo.
Merge pull request #415 from glogiotatidis/mozilla

Fix typo.
[Fix Bug 719925] Joining/Leaving group doesn't update the groups page
Merge pull request #416 from Sancus/719925

[Fix Bug 719925] Joining/Leaving group doesn't update the groups page
[fix bug 846678] Allow sorting of groups by number of members.
[fix bug 846488] [AP] Different Add and Change forms for Groups, Languages, Skills