1. Regardless of the type of input coordinate files, all conformations are now 
read in and immediately written to a binary DA scratchfile. This change in
readrtns.F

2. Subroutine work_partition has been split into proc_groups and work_partition.
proc_groups determines if the processors are split into the master and the
workers group. This is needed if there are secondary structure constraints,
in which case the master cannot do any energy calculations for efficiency
reasons. See also variable ntot_work.