gtk3-gi: Gtk::PlacesSidebar has been provided since gtk+3 3.10.0

only_gtk_version(3, 12, 0) ->
only_gtk_version(3, 10, 0)
                     ^
gtk3-gi: fix typo

Gtk::Places       OpenFlags::NEW_TAB ->
Gtk::PlacesSidebarOpenFlags::NEW_TAB
           +++++++
gtk3-gi: get/set_show_enter_location has been privided since gtk+3 3.14.0
webkit-gtk test: add check_version for WebKitGtk
Indent
clutter: add Clutter.check_version? method
clutter: require clutter/clutter
clutter test: define only_clutter_version for version sensitive test
clutter test: ClutterTestUtils module methods mark private
clutter: simplify
mkmf-gnome2: add detect and install packages for SuSE

* Experimental
* SuSE's rpm is usually provided same as Fedora's one.
clutter test: add Clutter::Canvas tests
clutter test: add Clutter::BrightnessContrastEffect trivial test

This class contains *_full methods.
It should change rubyish methods.
clutter test: add Clutter::ColorizeEffect test
clutter test: Clutter::Canvas#scale_factor accessor is provided since clutter 1.18
clutter test: add omit test

Travis CI's clutter expects Clutter::Color expects hash arguments. :<
clutter test: omit Clutter::Color in setup instead of individual tests
clutter test: add Clutter::DesaturateEffect test
clutter test: add Clutter::BulrEffect test

Clutter::BlurEffect.new returns Clutter::Effect if success
clutter test: fix typo

bulr ->
blur
 ^^