Fixed: rubytree gem breaks db:migrate:plugins (#4394).
Removes "xxx and return" calls (#4446).
Fixes test broken by r3176 (#4439).
Icons updates and cleaning.
Added missing translation for permission_view_issues (#4415).
Group icon changed on project members list.
IE8 fix.
Removes large icons.
Do not hide scroll buttons if some tabs are still hidden.
Adds auto overflow to content div.
