minor changes
Merge branch 'master' of https://github.com/mattam82/groupoid

Conflicts:
groupoid_interpretation.v
groupoid_interpretation_def.v
groupoid_utility.v
groupoid_utility2.v
remove trunc_eq

Conflicts:
groupoid_interpretation.v
groupoid_interpretation_def.v
groupoid_utility.v
groupoid_utility2.v
resolved conflict