NIFI-528 add support to specify timeout in ExecuteProcess

[medjessy]

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[jvwing]

@medjessy - Thanks for submitting this PR. The changes look larger than I would expect when comparing diffs. There appear to be a number of whitespace changes that make it difficult to review the commits. The GitHub UI presents the diffs as a 100% change (line endings?), but I also see what look like extraneous whitespace changes in IntelliJ. Do the diffs look right to you?

[MikeThomsen]

I wonder if this was done on Windows with the Git options not being set to "checkout w/ Windows line encoding, check in with Unix."

[joewitt]

Closing due to inactivity.