corerel: optimize overlayInsert perf

Instead of doing array.sort() for every insertion, do a binary search and insert. This works since the overlay is always sorted.

For an example model import, runtime was reduced from 2m11s to 37s.
Merge pull request #101 from webgme/overlayInsert_perf

corerel: optimize overlayInsert perf
Bump mongodb version. Fixes #102
unnecessary ordering completely removed
Add start script for npm
Added the Docker deployment option to the README.
Fix race with opening db connection
Read cache size from config
Fix small leak in event history
cacheSize===0 in config => dont use storage/cache at all
Merge branch 'master' into diff

Conflicts:
	src/common/storage/server.js