Fix the nextTick(cb) causing event loop starvation

If you run more than 1000 lookups (like processing a big directory of
files), you will get lots of warnings from node.  Solution is to use
setImmediate(cb) instead.
Added support for custom _id-s

As per issue #154, if the document to be inserted
already has an _id property, that _id will be used
instead of an automatically generated one.

I updated tests, browser builds and the README.
Move License from README to LICENSE.md. Fixes #183
Rename LICENSE.md to LICENSE
Merge pull request #184 from sbruchmann/fix/183

Move License from README to LICENSE.md. Fixes #183
Merge branch 'master' of github.com:mondora/nedb into mondora-master
One more test and recreate browser version
Bump version
Merge branch 'master' of github.com:szwacz/nedb into szwacz-master
Added a test
Bump version
Use last version of binary-search-tree module
Removed useless file
Can specify 2 or 3 args and still get desired results
Projection function added to cursor
Test with no or empty projection
Real test for empty projection and take-type projections
Real test for empty projection and take-type projections
Projection fully tested for cursor
Tested in find