Added Framework for Connect() and Listen()

Using the golang net package page as guidance, I implemented basic code for both Connect() and Listen().  Connect() connects to a specified address using the net.Dial() methods and if there is an error with the connection returns an error message.  Listen() creates a server and and begins to listen for any incoming connect requests; if there is an error in either creating the server or connecting to a requester an error message is returned.
Merge branch 'master' of https://github.com/Siacoin/Sia
Fixed up Status Message Typos and Other Stuff

Cleared up some typos that I made in status messages from the Connect() and Listen() methods in mutiplexer.go.  Also cleared up some syntax in Listen() to fix up what a status message returns.  Added some more status messages that gave more details at what the multiplexer was currently doing at that step such as in the Listen() and Connect() methods.
Merge remote-tracking branch 'ahmed/master'