Enhancement: Play all per subscription

[durango99]

Currently only the New Subscription has a context menu with Play All.

I've added code to allow all subscriptions to have the context menu with Play All. I've arbitrarily limited to play the last 150 videos to prevent channels with large number of videos to delay playing.

YoutTubeNavigation.py

    if (item("channel") or item("contact")):
        if (self.settings.getSetting("username") != "" and self.settings.getSetting("oauth2_access_token")):
            title = self.common.makeAscii(item("channel", ""))

            #ADDED
            cm.append((self.language(30520), "XBMC.RunPlugin(%s?path=%s&action=play_all&user_feed=%s&contact=%s&login=true&listlimit=true&)" % (sys.argv[0], item("path"), item("user_feed"), item("channel"))))

YouTubeFeeds.py

   while next == "true":

        index += 50

        #ADDED
       if get("listlimit") == "true" and index >=150:
            break

YouTubePlaylistControl.py

     #MODIFIED (add uploads)
     elif get("user_feed") in ["recommended", "watch_later", "newsubscriptions", "favorites", "uploads"]:

I do have some working code that will skip watched videos with the Play All feature. However, it's a direct sqlite query and I'm under the impression that JSON-RPC was the formal way to make sqlite database calls. So I'll leave that out for now.

EDIT: Also for now I did a fork on github and put in my changes if you were interested in looking at it.

Thank you