Merge pull request #2 from m-mcgowan/master

ARDUINO_HOME env var in include path
Updated instructions to compile the project
Fixed rotary encoder menu not working in fahrenheit

* Error in fixedToTenths: copy/paste job without updating the formula
* Error in tenthsToFixed: All multiplies before divides to prevent
rounding
* Error in menu.cpp: I was probably drinking beer when I programmed
that. That is not how conditional statements work!
Removed mode = beer constant from TempControl.init

This would set the mode to constant after loading the previous settings
from EEPROM. The correct behavior is to keep using the mode in EEPROM
Added shadow copy to LCD. Now works with no LCD connected

The OLEDFourBit class now always keeps a copy up to date of the LCD
content. The content does not have to be read from the display anymore.

I also set a maximum wait time on the waitBusy function, so that it is
non blocking.

These two changes make it possible to run BrewPi without a display
connected. The display in the web interface still works.
Better handling of disconnected sensors

- State will always be idle when a needed sensor is disconnected.
- Will try to re-initialize a lost sensor
Typo in compare statement (= instead of -)
Added a compiled binary for the Leonardo
Shield code, OLED display works through shift register

Still to update: rotary encoder
Rotary Encoder for shield. Only push button works so far and updated LCD init

Updated LCD init to be more universal
Partial commit, deleted some files accidentally
Recovery of unsaved changes after deleting files
Removed directory brewpi-avr
project file changed
Merge branch 'recovery' into shield

Conflicts:
	brewpi_avr.atsuo
	brewpi_avr/Display.cpp
	brewpi_avr/RotaryEncoder.cpp
	brewpi_avr/TempControl.cpp
	brewpi_avr/brewpi_avr.cpp
	brewpi_avr/brewpi_avr.cppproj
	brewpi_avr/pins.h
	brewpi_avr/temperatureFormats.h
New precompiled binary
fixed fridge setting from web and OLED LCD compatibility
Merge branch 'shield' of https://github.com/BrewPi/brewpi-avr into shield

Conflicts:
	compiled_binaries/brewpi_avr_leonardo.hex
New precompiled binary for Leonardo
Fixed buzzer on Arduino UNO