xcoh first working version

updates:
- subxcoh stores sdv in elem for output purpose
- output module updated for xcoh fstat and dm output

next:
-improve xcoh algorithms (and xbrick and xlam)
-map sdvs btw intg points of coh elems, allow xcoh and subxcoh to change
from elfail1 to elfail2/elfail3 (essential for migration problem)