Using Gtk3Reactor

Changed the PollReactor in flumotion/test/__init__.py to Gtk3Reactor
Added Gtk3Reactor to flumotion/common/testsuite.py
Made some changes to flumotion/component/common/streamer/streamer.py so flumotion/test/test_component_httpstreamer.py can pass one of two tests.
TestStreamDataNoPlug passes
TestStreamDataPlug get's skipped

track@track-HP-ProBook-4520s:~/Downloads/flumotion$ trial -r gtk3 flumotion.test.test_component_httpstreamer
flumotion.test.test_component_httpstreamer
  TestStreamDataNoPlug
    testGetStreamData ...                                                  [OK]
  TestStreamDataPlug
    testGetStreamData ...                                             [SKIPPED]

===============================================================================
[SKIPPED]
See #1137

flumotion.test.test_component_httpstreamer.TestStreamDataPlug.testGetStreamData
-------------------------------------------------------------------------------
Ran 2 tests in 0.013s

PASSED (skips=1, successes=1)

I think the skip is due to the indent left intentionally there. Don't know why tho.

TO DO:
*"localhost" in flumotion/component/common/streamer/streamer.py is wrong, need to correct that
* Find out what's with the skip above
*Try to figure out why test_common_gstreamer returns 2 fails on the Caps test