chore(travis): use gcc-4.8 in OSX
chore(travis): attempt to fix testcov build
chore(travis): attempt to fix testcov - 2nd try
chore(cmake): update the directories to remove in coverage measure
doc(osx-gcc): add known issue

[skip ci]
chore: add .gitignore
feat(filib): add fast interval library
test(nra): add new test
fix(realpaver): use eps in pruning