read Arduino IDE paths from config file

[mulderp]

Hi,

what do you think about having a .leorc file that contains the Arduino IDE paths similar to the variables in the https://github.com/sudar/Arduino-Makefile project?

For my current Arduino IDE 1.6 on MacOS, these are:

BOARD_TAG    = uno

ARDUINO_DIR   = /Applications/Arduino.app/Contents/Java/
ARDMK_DIR     = ../../
AVR_TOOLS_DIR = /Applications/Arduino.app/Contents/Java/hardware/tools/avr/
MONITOR_PORT  = /dev/cu.usbmodem14131
BOARD_TAG     = uno
AVRDUDE_CONF = /Applications/Arduino.app/Contents/Java/hardware/tools/avr/etc/avrdude.conf

I could add this feature to prevent this build error:

Cleaning build directory
Creating new build directory
   [build path] ./.build
Building basic as excutable.
  [compiler corePath]  /Applications/Arduino.app/Contents/Java/hardware/arduino/cores/arduino
  [runtime build extentions]  c,cpp,S
  [dir not found] /Applications/Arduino.app/Contents/Java/hardware/arduino/cores/arduino