add List.combine_chop and corresponding (and&) synchronized product

chore: remove travis to use github CI instead

add CCList.mguard function for list comprehensions

add some basic tests to CCMutHeap

un-specify order of elements in CCMap.to_list

Move definition of CCMap.update so that it is shadowed by Stdlib.Map.update

fix(intmap): order of arguments for the HO param should be stable

feat(containers-data): add CCMutHeap mutable heap with increase/decrease