Fix broken serial runs when Fix Frequency is specified
Merge pull request #51 from wortiz/fix-frequency-serial

Fix broken serial runs when Fix Frequency is specified
Fix VELO_SLIP BC in parallel when using a reference node to measure distance

Adds new functions to communicate boundary condition data that is needed in
parallel
Merge pull request #53 from wortiz/fix-velo-slip-par

Fix VELO_SLIP BC in parallel when using a reference node to measure distance