Use newer NAN
Use newer NAN

The build fails with nan <2.2.0. With the flat dependency tree in npm 3, if a peer specifies an earlier version that still matches ^2.0.0 (e.g. 2.0.9), then sse4_crc32 will use that and fail. (If there are no peers, then npm will install the latest.)

These changes from nan 2.2 are required:
https://github.com/nodejs/nan/compare/820a228...eca212b#diff-558c37be49a47656e3ff41806c24bd33R601
dudleycarr/sse4_crc32,Voxer/sse4_crc32,Voxer/sse4_crc32,dudleycarr/sse4_crc32,dudleycarr/sse4_crc32,Voxer/sse4_crc32,dudleycarr/sse4_crc32,Voxer/sse4_crc32