[vscode-concourse] support 'inputs' property for type 'PutStep'

[mstockd]

VSCode Extension version: 1.10.0 (4.3.1 Release)

The extension marks the key inputs as an unknown property if it is part of a put step definition.
https://concourse-ci.org/put-step.html#put-step-inputs

Example:

- put: a-put-step
   inputs:
   - some-input-name

[kdvolder]

Pushed a fix. It can be tried already from the snapshot builds. You can download it from here:

http://dist.springsource.com/snapshot/STS4/nightly-distributions.html

[mstockd]

Thank you! :)