GL-validate-raw-data: breaks if "R1" and "R2" are used as part of the sample name

[bnovak32]

Filenames that use "R1" or "R2" to indicate replicates or other information cause the sample number validation to break.

Given 14 file pairs with "R1" and "R2" present in the file name to designate the replicate number, GL-validate-raw-data returns the following error:

  We expected 14 forward read files, but 16 were found based on currently
  allowed read-pair designations (e.g. these formats: _R1_, _R1., -R1., -R1-,
  .R1., _1.). If it's not clear what the problem is here, share this use-case
  with Mike so we can expand functionality if needed.