WL-DASH-LASTSUCCBUILD

Add last successful build tag to widget

(Also small text change in 'WebLearn Status' title)
Cool so I can just do this:

def get_last_succ_build(job_name)
  last_succ_build_info = get_json_for_job(job_name, 'lastSuccessfulBuild')
  last_succ_build = '#' + last_succ_build_info["number"].to_s