Better groupId in pom.xml

Changed groupId to "net.kencochrane.raven" to describe project.  See http://maven.apache.org/ref/3.0.3/maven-model/maven.html#class_project
Change the groupId in the submodules to match the parent
Merge pull request #52 from ColinHebert/groupid

Change the groupId of the project
Add Colin Hebert to the developers
Set default configuration for the release plugin

To avoid any mistake, do not auto commit when doing a release:prepare
and use the version as the tag name
Fix tagNameFormat

Maven documentation says:
The tagNameFormat uses @{ and } as delimiters in order to ensure that
the default Maven property interpolation does not substitute the
values before the version transformation has taken place.
Set maven-release-plugin version

Some options are only available in recent versions of the plugin
use the last version currently available
Add more settings for the release plugin