* Complete rework of the driver's logic
* Added device name in log messages
* Modified default initialization sequence to
    's': stop streaming
    'v': reset board
    custom commands as per configuration in the GUI
    'b': start streaming
* Automatic port now scans available ports and picks first available
* Optimized drift estimation by sending a single block of sample
  per driver mainloop
* Implemented buffering when reading on serial port
* Updated switch/case parsing automaton to use enum values as states
  instead of integers (shuold be easier to read & maintain)
* Optimized the sample buffer array construction by pre-allocating it
  only once and filling the values by copy (no more sample-wise memory
  (de)allocation)
* Added parsing of board replies (when available) to get board
  information and possibly warn if unexpected return content is sent
* Added multiline support in additional commands
* Fixed bad parsing of accelerometers
* GUI: moved hidden widgets in an hidden window instead of hiding the
  widgets in the displayed window
* GUI: now shows feedback about configuration of the device (number
  of EEG channels, number Accelerometer channels, sampling rate)
* GUI: only shows com ports that can be opened, not all of them
  (usually reduces the list to only the OpenBCI board)
* GUI: exposed two different timeouts (see documentation for details)
* DOC: added one page documentation
* Fixed case / namings / indentation / whatever to comply with coding
  rules

Patch contributed by Yann Renard