fix(aalborg_theme): standardize padding on input and a buttons

Follow-up of #6591
fix(comments): makes ElggComment E_STRICT compliant

Gives ElggComment::canComment the same signature as the method in
its parent class.
Merge pull request #6658 from mrclay/canCommentStrict

fix(comments): makes ElggComment E_STRICT compliant
Merge pull request #6594 from PerJensen/aalborg_button_css

fix(aalborg_theme): standardize padding on input and a buttons and adds box-sizing
feature(groups): Added featured groups as a tab along with groups, popular, discussions

Slightly changed and combined work of @thuvalpakshi