[glide] Add new extractor

Added an extractor for glide.me shared messages.  Glide is a movile video messaging services.  You can share the link to the messages easily enough and this would allow you to download and save the actual video.

youtube_dl/extractor/__init__.py

@@ -134,6 +134,7 @@ from .gamestar import GameStarIE
 from .gametrailers import GametrailersIE
 from .gdcvault import GDCVaultIE
 from .generic import GenericIE
+from .glide import GlideIE
 from .globo import GloboIE
 from .godtube import GodTubeIE
 from .golem import GolemIE