Code changes to compile with gfortran

[dafyddstephenson]

Hi all, I have made some minor changes to the code that allow compilation with gfortran (as I'm currently using on my Mac) as well as ifort (as we're using on Expanse). In particular:

• String arrays are now such that all entries are of equal length. Over long lines containing string arrays are continued over multiple lines.
• Conditionals that check equivalence of a variable with a logical now use .eqv. (or nothing if checking for truth) instead of ==
• Conditionals that check true/false against an integer (taking 1 or 0) now explicitly check for var==1 instead of, e.g., if (var)

The changes shouldn't impact anything functionally.

[nmolem]

Thanks Davydd, I did look up the Fortran standard rules for dummy and actual arguments and while it's not super clear, it might very well be that the behavior of ifort to pad the actual arguments to make them equal length is not standard. I might look for a different solution to the problem, but in that case, I'll bring that up here. The current main branch on here is a bit out of date and some of the issues with logical operators have been taken care of already. I'll try to push those soon. As this is my first pull request, please allow for some time to get the procedure right.