gtksourceview3 sample: suppress warnings for deprecated API

test.rb:16:in `<main>': 'Gtk::SourceView' has been deprecated. Use 'GtkSource::View'.
test.rb:24:in `<main>': 'Gtk::SourceLanguageManager' has been deprecated. Use 'GtkSource::LanguageManager'.
gtksourceview3 sample: use more meaningful name

w      ->
window
 +++++
gtksourceview3 sample: use " (double quote) for string literal
gtksourceview3 sample: add executable permissions

    % chmod +x gtksourceview3/sample/{sourcelanguagemanager,test}.rb
gtksourceview3 sample: add a missing space after comma
gtksourceview3 sample: use "." instead of "::" for calling class method
gtksourceview3 sample: suppress warnings for deprecated API

sourcelanguagemanager.rb:13:in `<main>': 'Gtk::SourceLanguageManager' has been deprecated. Use 'GtkSource::LanguageManager'.
gi: convert GBytes to ASCII-8BIT string
gio2: support g_resources_lookup_data()
gio2: support g_resources_open_stream()
gio2: Add Gio::Resources.children
gio2: Add Gio::Resources.get_info
gi: raise returned all exception types
gio2: rename to Gio::Resources.enumerate_children

Because we use a naming rule that getter with argument needs verb.
Fill 2.2.0 entry
Use one line for one element
Update Ruby versions
gtksourceview3 test: add GtkSource::MarkAttributes test

TODO: remove tests for deprecated API.
gtisourceview3 test: remove a test

Because Gtk::SourceView#get_mark_category_background has been deprecated.
glib2 windows: upgrade bundled GLib

3.2.7  ->
3.2.12