Updates for bl_sam_t and bl_vcf_t API streamlining

Updates for biolibc and libxtend API improvements
Additional improvements to build system and documentation

Updates for evolving libxtend and biolibc APIs
Discard useless fields while reading SAM to improve speed
Improvements to test script
Add --version flag
Reduce hard limit on buffered alignments, assuming sanity filtering on SAM stream
Numerous other minor fixes and enhancements

Export sam_buff_t class to biolibc
Export remaining VCF functions to biolibc
Utilize libxtend functions

Redesign main loop to process all SAM alignments for each VCF call
Add hand-crafted test data
Add sort order checks
Factor out several functions to biolibc
Improve memory efficiency, now typically runs on 4-5 MB
Add MAPQ filtering with min MAPQ required on CLI
Collect stats on reads and alleles
Add script for clang profiling
Numerous other minor enhancements and bug fixes

Some SRA CRAM files contain an occasional 12th column in a a small number of alignments. This release adds a fix to tolerate and discard the extra data rather than take it as the first column of the next alignment.

Tested and stable on FreeBSD, RHEL, and Ubuntu.