Updated pom.xml, fixes jar generation

Without this, the generated jar does not contain any .class.
Merged remaining code from 3.3.0
Merge pull request #95 from uraimo/patch-1

Updated pom.xml, fixes jar generation
Changes in maven assembly and javagal conf

Modified assembly plugin configuration exclusion filters
Added javaGAL gui properties in linux launch configuration
Modified javaGAL configuration: now the network panID is automatically generated