Re-factored SideSetsAroundSubdomain (closes #2844)
Moved tests from output to outputs (close #2591)
setOutputPosition() -> parentOutputPositionChanged()

This function (on both FEProblem and Executioner) no longer sets the
output position, it just calls parentOutputPositionChanged(), so it no
longer needs to take a Point, and I'm changing the name in both
FEProblem and Executioner.

Refs #2912.
Merge pull request #2908 from aeslaughter/sideset-2844

Re-factored SideSetsAroundSubdomain
Merge pull request #2911 from aeslaughter/tests-2591

Moved tests from output to outputs
Merge commit '08ac9a642607426ce51efb26a4cd01d9ed034af7'
Merge pull request #2913 from jwpeterson/set_output_position

setOutputPosition() -> parentOutputPositionChanged()
Merge commit 'a1859b4f7859baa858bdea05c56dbbcb8a7f089c'
Merge commit '7a87dcbd3bb24ae61b462bf0cdb4cd9fd3b0e5e7'