Added processing queue for messages

Conflicts:
	barter.li/src/li/barter/chat/ChatService.java
Removed Handler for chat processing since callbacks are delivered on the main thread
Loading images for users

Conflicts:
	barter.li/src/li/barter/chat/ChatService.java
Fixed crash when trying to display images
Temporarily disabled chat profile picture loading to fix crash
Chat profile pics
adding facebook login
Merge branch 'contributions' of github.com:barterli/barterli_android into contributions
Changed to use image_url from servcer
Merge branch 'contributions' of github.com:barterli/barterli_android into contributions
Disposing connection when ShutdownSignalException occurs
Fixed extreme battery usage if disconnected from the internet after connecting to chat
Merge branch 'contributions' of github.com:barterli/barterli_android into contributions
Added auto-reconnect with exponential backoff to chat connection. If the first connect attempt fails, it will try again after 5 seconds. If that fails, it will attempt after 10, then 20, then 40 seconds and so on uptil a maximum of 15 minutes. Any explicit connect attempts(log in, network resumed) will reset the timer and attempt to connect immediately
Added autoreconnect if chat service disconnects after already conneted
Updated to use milliseconds for connecting to chat
Reading book info from server, removed publication month & year
added login through facebook
Merge branch 'contributions' of github.com:barterli/barterli_android into contributions
Moved Hangout.java to models package