Presync

ML_BSSN was modified to use Presync instead of the Boundary thorn.

ML_BSSN was changed to use Presync, including the void->int change inside Presync.

This adds some extern statements for use of Presync.

Changing ML_BSSN and ML_BSSN_Helper to use presync.

Updated ML_BSSN to use PreSync and new macros. Test par files changed to turn on PreSync.

Fixed scheduling for boundary condition selection function.

Fixed typo in new macro.

Changed test to use Boundary2.

Fixed Read/Write declarations in ML_BSSN_Helper

Removed unneeded GROUPs in ML_BSSN scheduling

Updated macros to match changes in rdwr.pl

Updated for changes to BC scheduling groups

Implemented PreSync backward compatibility changes

Removed unnecessary dependency on Boundary

Moving the presync parameters to the flesh

Checkpointing

Edited reads/writes.

ML_BSSN: do not trigger SYNC before EnforceEverywhere

this restores current behaviour in ML even if the routine does actually read and write from and to everywhere

Use psync

Get rid of psync vars in test parameter files

Removed repeated activation of thorns in parameter files