[FIXED JENKINS-25358] Remove extra fields from getFieldOrder()

Remove fields which are not part of struct _SHELLEXECUTEINFO.
Use a jna Union type for the DUMMYUNIONNAME union structure

JNAerator ( https://code.google.com/p/jnaerator/ ) was helpful
for generating the Java code from the C struct.
Merge branch 'JENKINS-25358' of github.com:rodrigc/jenkins
[JENKINS-25358] Noting merge of #1445.
the trunk is toward 1.589-SNAPSHOT
Merge remote-tracking branch 'origin/master'
Adjust my prior change to better utilize structured form submission to accomodate a plugins that are not using p:config-assignedLabel
mark the legacy jelly endpoints as DoNotUse
Merge pull request #1447 from mattmoor/labels

Adjust my prior change to better utilize structured form submission...
merged back the RC branch
creating an RC branch