Utils: added gstreamer utils

    * .gitignore: added .deps directory from utils to ignored list
    * Makefile.am:
    * configure.ac: added utils to a build system
    * src/utils/Makefile.am: makefile of utils module
    * src/utils/gstreamerutils.{cpp|h}: implemented a few helper methods
      (get_object_info, parse_caps).