Merge pull request #2 from colincross/master

Don't print bell character and add .gitignore
Add 57600 baud rate
Merge pull request #3 from machinaut/patch-1

Add 57600 baud rate
Switch the serial port to blocking after opening

The serial port must be opened non-blocking to avoid waiting for
carrier detect during open, but leaving it set to non-blocking
causes later writes to fail with "Resource temporarily unavailable".
Switch the fd back to blocking mode after opening.