Common test methods are moved to a module

 * New namespace module Bio::TestClustalWReport.
 * Common test methods are moved to CommonTestMethods,
   and test classes using the methods include it.
 * The test_sequences method is split into two methods
   CommonTestMethods#test_sequence0 and test_sequence1.
Simplify test data path in setup

 * Bio::TestClustalWReport::TestClustalWReport#setup: simplify test data
   filename path.
 * Modify indentes and void lines.
New test data: ClustalW with -SEQNOS=ON option

 * test/data/clustalw/example1-seqnos.aln: New test data: ClustalW
   running with -SEQNOS=ON option.
 * Bio::TestClustalWReport::TestClustalWReportSeqnos: new test class
   that parses the above data.
Bio::ClustalW::Report#do_parse speed optimization

 * Bio::ClustalW::Report#do_parse speed optimization. Thanks to
   Andrew Grimm who indicates the optimization point.
   (https://github.com/bioruby/bioruby/pull/86 )
 * "$" in the regular expression is changed to "\z". In this context,
   the "$" was intended to be matched with only the end of the string.
Add benchmark script for Bio::ClustalW::Report.
Benchmark example1-seqnos.aln in addition to example1.aln

 * sample/benchmark_clustalw_report.rb: Benchmark parsing speed of
   example1-seqnos.aln in addition to example1.aln.