Add `genome disk allocation purge` CLI

It requires a `reason` and a list of `Genome::Disk::Allocation` objects.
clarify help_detail to roughly describe purging
use sprintf style status messages
differentiate help for Purge and Deallocate
allowing user to input insert size params without being overridden
remove spurious 'my', simplify insert size checking
Merge branch 'master' of https://github.com/genome/genome into bsmap
Merge pull request #331 from mark-burnett/add-purge-command

Add `genome disk allocation purge` CLI
Merge pull request #339 from chrisamiller/bsmap

allowing user to input insert size params without being overridden
updated jenkins submodule to ad020c5
New way to read a bam-readcount file

Assuming that the file is sorted by position, this allows you to
get entries by position.  You have to read the positions almost in
order, although you can look back into a buffer of one entry.
We need this because vcf entries can look at multiple bam-readcount
entries, depending on whether they have deletion alternate alleles.
Move bam-readcount vcf-safe encode and decode to a separate class
Factor out is_deletion
create_deletion_entry is always called with bam_readcount_line_deletion

Don't need to pass it as a param or export/import it
Bam readcount test helper gets entries from vcf files
Add a bam readcount parser that can encode and decode bam-readcount lines in vcf

Lines from bam-readcount are stored in a sample format field as json.
The json contains a hash with two types of keys:
-alternate alleles.  The values of these entries point to which offset key
should be checked to find the bam-readcount line for that allele.
-offsets.  The key is the offset from the vcf position on this line (since
bam readcount interprets deletion start positions differently, they will be 1; all
other types of normalized vcf alleles will be 0).  The value is the bam-readcount line.

The json is made vcf sample field safe using the encode function
Correctly mock up test data

The single-bam ("normal") build should return the alignment
result from the normal sample as its merged_aligned_bam_result
Use the new BamReadcountParser to get allele-specific bam-readcounts from vcf

-gmt annotate-with-readcounts now uses BamReadcountParser
-update all of the interpreters and filters that use bam-readcount to
handle bam-readcount entries on a per-allele and per-sample basis rather than on a
strictly per-sample basis.
Test doesn't actually depend on bam-readcount

Since the test is just using the bam-readcount test helper
as a convenient way to make a vcf entry, use the simpler
entry that doesn't actually contain bam-readcount output