pysam-0.8.4

This release contains numerous bugfixes and a first implementation of
a pythonic interface to VCF/BCF files thanks to Kevin Jacobs.

Potential isses when upgrading from v0.8.3:

• binary tags are now returned as python arrays
• renamed several methods for pep8 compatibility, old names still retained for
  backwards compatibility, but should be considered deprecated.
  • gettid() is now get_tid()
  • getrname() is now get_reference_name()
  • parseRegion() is now parse_region()
• faidx now returns strings and not binary strings in py3.
• The cython components have been broken up into smaller files with
  more specific content. This will affect users using the cython
  interfaces.

A full list of changes is at http://pysam.readthedocs.org/en/stable/release.html