Make jobs suffix = stream (eg 4.2.luna instead of 42)

In order to reduce the amount of conventions and allow better factorization, we should get rid of the current convention (jobname_42) on job/nightly-build/staging names and replace it by the same convention as composite and aggregate site (4.2.luna).
For example:

• jbosstools-central_42 => jbosstools-central_4.2.luna
• as a consequence download.jboss.org/jbosstools/builds/staging/jbosstools-central_42/ => download.jboss.org/jbosstools/builds/staging/jbosstools-central_4.2.luna/
  And
• devstudio.product_80 => devstudio.product_8.0.luna