Added support for boards and simple quality check

- new js-file (espruino.board.js)
- Listbox added for selection of board
- load connection data from www.espruino.com
- prepare data for internal use
- created json data for position of pins, using a hack in files from
www.espruino
- recalculate size for images of boards to fit into editor window
- if data is loaded, a new button, right of selectbox, which opens a
form
- image of board on right
- tree on the left for all devices
- mouseover on tree in 2nd/3rd level adds overlay balls for all possible
pins
- if parameters ( something like /*function,pinfunction*/pin ) are set
an additional button right in editor part
- a table of all parameters
- a click in parameter in source sets selection on full parameter
- dblclick on this selection opens image of board with
- all possible pins with a orange ball, and already used pins with tan
ball
- click on a ball replaces old assigment to new one in editor source
- new function in espruino.general (ShowSubForm)
- added "use strict"; in all source files for quality reason, except
serial
- one function in serial should be relocated as far as I understand
message

Known problems are:
- location of pins is based on board reference in Espruino.com, which is not 100% correct
  actual boards tested are Espruino/STM32F4Discovery, take a look to top pins of Espruino to see the problem
- board list is hardcoded and should be created by reading folder, but I don't know how
- some items in new JSON board files are strange, at least for me
- tested by Juergen, .... only
- should we add an option to switch this new function on/off ?