Reset essential package list to an empty set when Packages is refreshed
misc/bcfg2.spec:  Bump release

Forgot this somewhere; already bumped in %changelog
Metadata: fix check for Groups with options in duplicate groups test
Merge pull request #155 from zultron/maint

misc/bcfg2.spec:  Bump release
Merge pull request #149 from danfoster/apt-essential-cache

Essential package list cache is not cleared when Packages is refreshed
Core: explicitly close database connections at the end of each client run
misc: build requires gamin-python to properly generate docs
doc: fixed code-block style for older sphinx
misc: only require gamin for building on RHEL < 7
redhat: wait longer before kill -9'ing bcfg2-server
settings: Make it possible to use ibm_db_django engine

This is a forward-port of 49362b6d633a7784f77650d5218d0e629d50e4fb
doc: Only a single spec file exists now

Signed-off-by: Sol Jerome <sol.jerome@gmail.com>