Started conversion of Handshake protocol to transport interface

Also changing Handshake servers interface to Message Channel API
Converted handshake server interfaces to Message Channel interface
Renamed Mandshake object references to HandshakeManager
Changed handshake references for routing for transports
Converted routing protocol in a transport interface (needs testing)
Removed private functions to avoid confusion
User interface shows UID from PeersManager
Routing transport protocol working over handshake servers
Shortcut on transport.sendAnswer if sending to a handshake server
Started support to search files by hash
Refactored HandshakeManager errors
Allow backup of cache after handshake disconnection if there's no peers
Close peer when DataChannel gets closed
Added snippet for Small files acelerator specification
Fixed bug not showing the remote peer selector pop-up
Check early if messages have been routed by a peer
Merge branch 'master' into issue_72__Convert_handshake_to_be_a_transport_interface
Only send fileslist updates if required when requesting the fileslist
Define on what tabs container should the tab de added
Close each tab individually instead of with a tabs global function