Update MANIFEST.in to exclude DOCKER, .github and other unnecessary
files for release.
include README.md LICENSE ChangeLog INSTALL.md MANIFEST.in setup.py bin/macs2 MACS2/cPosValCalculation.c MACS2/cStatistics.c
recursive-include MACS2 *.py *.pyx *.pxd *.c *.h
+exclude .gitignore .travis.yml
prune test
+prune .github
+prune DOCKER
