Releasing 0.7.0-p4

Update version

Merge pull request msgpack#152 from msgpack/nested-map

Fix a bug when creating nested maps and arrays

Fix msgpack#145: msgpack-{core,jackson}-0.7.0-M5 release. Fix sbt scr…

…ipts to allow multi-module project deployment

Fix multi bytes decoding error at boundary

Add mitsu to the developer list

[maven-release-plugin] copy for tag msgpack-0.6.11