gt3-gi: remove garbage ";"
gtk3-gi: implement Gtk::SearchBar
gtk3-gi: fix Copyright year

2006-2014 ->
     2014
^^^^^
gtk3-gi: remove `Gtk::SearchBar#handle_event?`

Because GDK_EVENT_STOP and GDK_EVENT_PROPAGATE provides for readability.
So, it should not treat as predicate methods.
support Gemfile.local.

Because nokogiri is too fragile gem.
rake-compiler is usually installed system wide.
And this change makes to be able to write `nokogiri` and `rakecompiler` etc.
 setting into Gemfile.local at on your risk.
So it is reasonable to split Gemfile and Gemfile.local.