The ChangeLog automation scripts were incorporated in gnulib as
vcs-to-changelog for a while now since other projects expressed the
desire to use and extend this script. In the interest of avoiding
duplication of code, drop the glibc version of gitlog-to-changelog and
use the gnulib one directly.
The only file that remains is vcstocl_quirks.py, which specifies
properties and quirks of the glibc project source code. This patch
also drops the shebang at the start of vcstocl_quirks.py since the
file is not intended to be directly executable.
