fix(zbud6): fixed filename extension case

[timcera]

The files "compilerversion.f90" and "defmacro.f90" should have instead the extension ".F90".

[codecov[bot]]

Codecov Report

Merging #116 (2a297a8) into master (a46a7db) will decrease coverage by 11.910%. The diff coverage is n/a.

:exclamation: Current head 2a297a8 differs from pull request most recent head 9965c75. Consider uploading reports for the commit 9965c75 to get more accurate results

@@              Coverage Diff               @@
##            master      #116        +/-   ##
==============================================
- Coverage   62.355%   50.445%   -11.911%     
==============================================
  Files           18        18                
  Lines         4492      4492                
==============================================
- Hits          2801      2266       -535     
- Misses        1691      2226       +535     

Impacted Files	Coverage Δ
pymake/pymake.py	72.222% <ø> (-3.704%)	:arrow_down:
pymake/plot/dependency_graphs.py	11.688% <0.000%> (-57.143%)	:arrow_down:
pymake/utils/_Popen_wrapper.py	60.000% <0.000%> (-30.000%)	:arrow_down:
pymake/autotest/autotest.py	2.482% <0.000%> (-24.658%)	:arrow_down:
pymake/pymake_base.py	73.745% <0.000%> (-12.999%)	:arrow_down:
pymake/utils/_compiler_switches.py	71.397% <0.000%> (-9.171%)	:arrow_down:
pymake/utils/download.py	62.571% <0.000%> (-6.858%)	:arrow_down:
pymake/utils/_usgs_src_update.py	82.044% <0.000%> (-3.315%)	:arrow_down:

[langevin-usgs]

Thanks for this PR! Pulled it in, even though there was a RTD failure. Looked to be due to an unrelated sphinx theme issue.