Update of plugin versions.

Update of plugin versions in central pom of NEST.

Notes:

- versions of assembly and compiler plugin would brake the build process, and cause problems in packaging with the latest maven 3.1.1 and jdk 1.7.0_45.
- tested compiling and assembling with this pom on linux64 and win64.
- other plugin versions I do not think are critical, still I updated their versions.