master :: forc_typ = 6 LDASIN issues

[jmccreight]

master branch
force_type = 6
I am not doing anything to fix this for now, but this needs to be discussed and documented.

The behavior when LDASIN files are missing is undesirable in several ways:

1. Apparently any file at t+12 hrs will be used if t is missing (My opinion is that this is bad and the user should be forced to fake these with symlinks and handle before run time at the system level. The potential cost of runs that look fine but read completely different LDASIN files than expected is too high to leave this as the default.)
2. Diagnostics barely reflect when this is happening unless you read all the image print statements for a given time: the filename actually read in is not communicated to the other images so the diagnostics are misleading.
3. No warning is produced when a different time is substituted for the current time. Given 1, this would not be necessary. But if somehow the current behavoir is desirable, then a warning should be printed at a minumum.