Parameter file in snapshot

Sorry @pdraper.... one more for you...

This is an implementation of #140 (closed). The parameter file key-value pairs are written to the snapshots. Changes are:

• Write the parameters to the snapshot.
• Reduce the size of the parameter file structure by changing the maximal amount of lines it can contain.
• Added an error message for when this limit is reached.
• Change the type lock_type to swift_lock_type in lock.h

This last change is because lock_type is used in some MPI function prototype and our "#define" interferes with some of the includes if you are not careful about ordering. That solves the problem by naming the lock type in a unique way.

Apologies for the rather large changelog that this generates for 5 actual lines of useful code...