feature(file): display file upload limit on file upload form

Refs #6355
feature(groups): Added featured groups as a tab along with groups, popular, discussions

Slightly changed and combined work of @thuvalpakshi
chore(ci): Encrypted notification email

This is to avoid receiving notification from forks. See http://docs.travis-ci.com/user/encryption-keys/
Merge pull request #6877 from Srokap/notification_email

chore(ci): Encrypted notification email
fix(docs): Inline refs use @link instead of @see

Inline references in documentation should use {@link ...}
Merge pull request #6881 from Srokap/pr/6871

fix(docs): Inline refs use @link instead of @see
fix(notification): extract notification summary from $params

Fixes #6885
fix(aalborg_theme): inconsistency between owner-block and page menu
Merge pull request #6887 from PerJensen/aalborg_menu

fix(aalborg_theme): inconsistency between owner-block and page menu
fix(aalborg_theme): show dashboard menu item only when logged in

Fixes  #6049
Merge pull request #6898 from PerJensen/1.9

fix(aalborg_theme): show dashboard menu item only when logged in
fix(aalborg_theme): Support fullscreen mode if user adds app to homescreen

Fixes #6896
Merge pull request #6904 from ewinslow/mobile-web-app-capable-b6896

fix(aalborg_theme): Support fullscreen mode if user adds app to homescreen
fix(aalborg_theme): emphasizes sidebar navigation

Fixes #6874
Merge pull request #6915 from PerJensen/aalborg_sidebar_navigation

fix(aalborg_theme): emphasizes sidebar navigation
chore(release): Remove usage of pushd and popd

Reasons:
1. Not all environments have these (e.g. codio.com).
2. Ending at the root directory of the new branch seems more correct
   than bouncing back to a potentially unrelated directory.
chore(gitignore): Ignore startup.sh, which has special meaning to codio.com
chore(release): install and update node deps before each release
chore(release): continue even if release branch is already created

With git branch/git checkout the script would fail if you had run
it once already and the release branch had already been created.
This makes it so it ignores the fact that the release branch has
been created and just continues on its merry way, which is a more
intuitive behavior than forcing you to clean up the environment
if the script fails the first time.
chore(docs): make tx install command code instead of italics