Update eeprom.c

Function eeprom_put_char's parameters did not align with the .h file.
Update gcode.c

home_select defined out of scope. Moved it outside the switch 
so the rest of the switch can see it properly. 
Update eeprom.c

Changed back
Update eeprom.h

Fixed the function signature.
Update gcode.c

Removed the home_select variable.
Merge pull request #200 from Protoneer/master

Fixed small bug.
G-code updates for G10 L2 and L20

- Updated g-codes G10 L2 and G10 L20 to the new descriptions on
linuxcnc.org
Update README.md
Increased g-code parser line buffer. Added line overflow feedback.

- Increased g-code parser line buffer from 50 to 70 characters. Should
fix most all issues with long arc statements, provided that they are 8
digits(float) long only.

- Added a line buffer overflow feedback error to let the user know when
it encounters this problem. Resets the line whenever this occurs.
(Thanks @BHSPitMonkey!)
Updated readme