Remove annoying browser dialog box about leaving page

See http://wordpress.org/support/topic/bug-leave-page-dialog
Elusive Icon Font

https://github.com/aristath/elusive-iconfont
Merge pull request #9 from kucrut/7-elusive

Elusive Icon Font
Update Supported Icon Types in readme
Merge branch 'develop' of github.com:kucrut/wp-menu-icons into develop
Update readme.md
Update .POT
Protect meta key
Print notice when no registered icon types found
Settings meta box
Implement settings reset
Don't load non-active icon type style
Implement Extra stylesheet from settings

This removes menu_icons_load_extra_style filter
Implement default position setting
Fix custom walker filter
PHPDoc & PHPCS fixes
Update Form Fields

* Streamline 'keys'
* Add new types: number, url, color, date
* Support inline description (using <span /> instead of <p />)
Helper: Introduce kucrut_validate()
Plugin & Menu settings in-a-box
Fix typo in settings messages