fix enstops being defiened as nc, so an nc endstop axis will not home
fix checking for min or max endstop
Merge branch 'fix/endstops-nc' of https://github.com/wolfmanjm/Smoothie into fix/endstops
Merge pull request #155 from wolfmanjm/fix/endstops-nc

fix endstops being defined as nc, so an nc endstop axis will not home
Merge remote-tracking branch 'upstream/edge' into fix/endstops