Add initial video playback support for Ogg Theora videos (resolves issue #66.)

The basic APIs are:

video = love.graphics.newVideo("myvideo.ogv")

love.graphics.draw(video, ...) -- Video objects are Drawables.

video:play(), video:pause()

video:getDuration(), video:tell(), video:rewind(), video:seek(seconds)

video:getSource()

video:getWidth(), video:getHeight(), video:setFilter(min, mag)

More advanced APIs include video:setSource(source), video:getStream(), and videostream:setSync.

To use a custom pixel shader when drawing a Video, call the new TexelVideo(texcoords) function instead of Texel(texture, texcoords) in order to get the pixel colors of a video frame.

src/modules/graphics/opengl/wrap_Video.lua

@@ -0,0 +1,69 @@
+R"luastring"--(
+-- DO NOT REMOVE THE ABOVE LINE. It is used to load this file as a C++ string.
+-- There is a matching delimiter at the bottom of the file.
+
+--[[
+Copyright (c) 2006-2015 LOVE Development Team
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+claim that you wrote the original software. If you use this software
+in a product, an acknowledgment in the product documentation would be
+appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+--]]
+
+local Video_mt = ...
+local Video = Video_mt.__index
+
+function Video:loadRemote()
+	local stream = self:getStream()
+	local remote = love.video.newRemote()
+	stream:setSync(remote)
+	return remote
+end
+
+function Video:setSource(source)
+	self:_setSource(source)
+	if source then
+		self:getStream():setSync(source)
+	else
+		self:getStream():setSync(love.video.newRemote())
+	end
+end
+
+function Video:play()
+	return self:getStream():play()
+end
+
+function Video:pause()
+	return self:getStream():pause()
+end
+
+function Video:seek(offset)
+	return self:getStream():seek(offset)
+end
+
+function Video:rewind()
+	return self:getStream():rewind()
+end
+
+function Video:tell()
+	return self:getStream():tell()
+end
+
+function Video:isPlaying()
+	return self:getStream():isPlaying()
+end
+
+-- DO NOT REMOVE THE NEXT LINE. It is used to load this file as a C++ string.
+--)luastring"--"