adding test to illustrate bug with get_revision with no scm
Fixing get_revision with no scm
Fixed kerberos request's interface
Linter fixes
Low level api change to support tree api
Changed job and build modules to use tree api
Replaced _poll_if_needed with lightweight tree calls
Added support for JENKINS_URL env. variable
Added use of tree api to node, job, queue and fixed tests
Pylint fixes
added decode to test to make it work in PY 3.x
Merge pull request #313 from lechat/tree_api

Tree api