Re-enable filament menu with recalc fix when enabling/disabling mm3

replaced ASCII GPL v3 license by markdown version

moved new COPYING file to top-level directory to make it more visible and remove clutter from Marlin subduer

Cleanup and refactoring of termistor LUT generator (fixes bug #1305)

refactored termistor table calculation to be in line with wikipedia's article about Steinhart-Hart coefficients

This reverts commit dd7e4ee9.

This reverts commit 2b9722f3.

issue 968 for dev branch

try, try again.

If 'OK' is garbled on sending PC won't receive it.  Both machines will
wait on each other forever.  This resends OK if nothing is heard from PC
for a while to avoid this bad case.

temp runaway: proper cast to prevent any overflow.

Define analogInputToDigitalPin only if needed

Added further tests to Travis CI config

Fix for cant compile when REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER ...

Readd .travis.yml

Added .gitignore back into repo