use typeof "function"
fixed; model.remove() removes only what is necessary

fixes #1649
release 3.7.2
docs; fix indexes link

closes #1648
now working on 3.7.3
Promise support for geoNear

added promise support for geoNear & accompanying tests #1614
geoSearch promise support; refactoring of tests

geoSearch & geoNear tests refactored. Additionally, callbacks now have
appropriate parameters based on the API. Seeing weird things happen in
the tests like failed assertions not happening, ect. Also, the 2.4 check
isn't working for some reason. Before() doesn't happen
refactoring tests on geoSearch
fixed up tests; couple small promise bugs
docs; state which branch is stable/unstable