Catch exceptions if vcf result is not available
Throw exception if files don't exist
Catch exceptions if vcf results don't exist

There may be builds without vcf results, so
we can catch those exceptions and simply return
undef.
Get original string from bam-readcount entry
Command to add readcount to vcf sample fields

We assume that all readcount files are sorted in
the same order as the vcf file, and that they contain
only variants in the vcf file.
Remove unneeded temp variable $results
Add abstract methods to abstract class Adaptor
Improve tests for Adaptor::SomaticVariation
Merge branch 'updated' into gb_master