adds txt file suite

Author: BWMac

src/dcqc/suites/suites.py

@@ -45,3 +45,7 @@ class BAMSuite(FileSuite):
 class FastqSuite(FileSuite):
     file_type = FileType.get_file_type("FASTQ")
     add_tests = (tests.PairedFastqParityTest,)
+
+
+class TXTSuite(FileSuite):
+    file_type = FileType.get_file_type("TXT")