Validate sequence files:
Validate valid 1st sequence header character is expected character
Validate fastq files have same number of bases and quality scores per read
Remove reads below minimum threshold: "seqFileValidator.seqMinLen"
Trim reads if above the maximum threshold: "seqFileValidator.seqMaxLen"
Invalid reads are saved to a file in the module temp directory for analysis/review.
Typically we verify no duplicate file names are used, but for QIIME we may be combining multiple files with the
same name ("otu_table.biom"), so QiimeClassifier skips this validation.
Verify equal number of forward and reverse read files.
if "seqFileValidator.requireEqualNumPairs"="Y", verify forward and reverse read files have
an equal number of reads.