JBIDE-18323 : support for .jboss-maven-repository marker

Refactored local repository detection quite a bit.
Now repositories can be identified with a .jboss-maven-repository marker, following the java.util.Properties file format (key=value).

The marker should contain :
- repository-id : repository id
- name : human readable repository name
- profile-id : maven profile id this repository will be activated from.

if profile-id is missing, we fall back on repository-id.
If name is missing, we fall back on repository-id.
if repository-id is missing, we fall back on name.
if repository-id and name are both missing, the marker is ignored
 

Signed-off-by: Fred Bricon <fbricon@gmail.com>