move commons to lib_funs
more tests
two test cases are still failing on index
is_ready/1 added
added remark about clang
Merge branch '0.6.0' of github.com:fisher/yalinka into 0.6.0

forgot to sync first thus merge
insert/2 working sketch
roadmap added
sketch for compare/2
sketch for compare/2
compare/2 works
added some visualization helper tools
roadmap view
fix tests before merge into master
Merge branch '0.6.0'
unified "invalid reference" reporting
doc++
struct renamed
trying to make common data types for 3d and kd
version bump