ABlog for Sphinx: ABlog v0.7.6 released

ABlog v0.7.6 is released to fix path resolving issue that arose when :excerpts: is used in postlist directive. Once again, thanks to Peter Mills for reporting this issue. Other minor changes are:

• -P argument is added to ablog build command to enable running pdb on exceptions.
• conf.py file created by ablog start updated to include about.html sidebar that comes with Alabaster theme.