add search function in playlist view.
add search method in library view.
add git ignore.
add search shortcut 'Ctrl+F'
fix bug: search box can not escape.

Esc key to unfocus search box and focus main view.
fix bug: search_unfocus typo.
fix bug: on wxMac 2.9, search method does not work in library view.
fix bug: "Search" box is not translated.
Merge branch 'add-search' of github.com:meiraka/music_controller into add-search
Merge pull request #1 from meiraka/add-search

Add search