Update declarations for PROGREM, to build with avr-gcc 4.8.1 / Arduino 1.5.7

- PROGMEM error: avr-gcc 4.8.1 reports:
  variable ... must be const in order to be put into read-only section by means of ‘__attribute__((progmem))’
  and the fix is to make the variable 'const'

- also add ifdef to support non-US date format (D/M/Y)
Fixes to build with Arduino 1.5.7, Processing 2.2.1

- PROGMEM error: avr-gcc 4.8.1 reports:
  variable ... must be const in order to be put into read-only section by means of ‘__attribute__((progmem))’
  and the fix is to make the variable 'const'

- Processing has changed selectInput to a callback

- also add ifdef to support non-US date format (D/M/Y)
Merge branch 'master' of https://github.com/bdlow/TIMESQUARE-Watch
Merge branch 'master' of https://github.com/bdlow/TIMESQUARE-Watch
Merge branch 'master' of https://github.com/bdlow/TIMESQUARE-Watch
Update the Processing helpers to include 'const'.
Merge pull request #1 from bdlow/build-fixes

Build, Processing selectInput and date format fixes