token expansion in nodes filter

(from [c1137d39a3c8c6a895d28a7d06dc1d63086a42d1]) Add support for variable expansion in job node filters. (pull req #39) [#235 state:needs_verification] https://github.com/dtolabs/rundeck/commit/c1137d39a3c8c6a895d28a7d0...

The fact that this is allowed now needs to be added to documentation

I tested this with this job:

- id: filter-variable-expansion-test1
  project: test
  loglevel: INFO
  sequence:
    keepgoing: false
    strategy: node-first
    commands:
    - exec: uname -a
  description: ''
  name: testjob1
  uuid: filter-variable-expansion-test1
  nodefilters:
    dispatch:
      threadcount: 1
      keepgoing: false
      excludePrecedence: true
    include:
      name: ${option.hosts}
  options:
    hosts: {}

It sort of works. I get this message when I get to the execution screen:

Warning: The Node filters specified for this Job do not match any nodes, execution will fail.

1. If I use the ajax version of the green Play button from the jobs list (opens in same page), then clicking Run Job Now does absolutely nothing (the dialog closes and I get back to the normal jobs page)
   
2. If I middle click (open in new tab) the green Play button and run it from there, I still get the warning message but the job works.

i believe your problem 1: was just that the page might not update to reflect the executing job if it finishes quickly.

Adding documentation.

(from [b2db43936473052bf2f69b8ebc727b28ef132826]) Add documentation about dynamic node filters via token expansion. [#235 state:needs_verification] https://github.com/dtolabs/rundeck/commit/b2db43936473052bf2f69b8eb...

Verified in http://build.rundeck.org/job/release-1.3-rc/99/