Collect hardcoded literals into constants

[bartnijssen]

Replace hardcoded literals, such as

character(LEN=256) by character(LEN=STR_SIZE)
12 by MONTHS_P_PYR

etc. to improve readability and maintainability

[martynpclark]

Also the notPopulatedYet strings

[martynpclark]

Also nBands and nTimeDelay