While I was looking around since I'm making a pack for a friend and found a converter from 1.5 to 1.6 and is really handly.
1.5 > 1.6 Texture to Resouce Pack - http://s3.amazonaws.com/Minecraft.Download/utilities/TextureEnder.jar
If you have a texture back before 1.5 you will need to use - http://assets.minecraft.net/unstitcher/unstitcher.jar Before using the TextureEnder one.
This information was found on http://www.minecraftwiki.net/wiki/Resource_pack
1.5 > 1.6 Texture to Resouce Pack - http://s3.amazonaws.com/Minecraft.Download/utilities/TextureEnder.jar
If you have a texture back before 1.5 you will need to use - http://assets.minecraft.net/unstitcher/unstitcher.jar Before using the TextureEnder one.
This information was found on http://www.minecraftwiki.net/wiki/Resource_pack