Make sure portage doesn't ask for confirmation

If EMERGE_DEFAULT_OPTS in make.conf(5) contains '--ask' then the portage
module doesn't work correctly, this commit fixes that
fix at.py module on non-glibc systems
Merge remote-tracking branch 'upstream/devel' into devel
Merge remote-tracking branch 'upstream/devel' into devel
Merge pull request #161 from lifanov/devel

fix at.py module on non-glibc systems
Merge pull request #129 from soeren2342/devel

Make sure portage doesn't ask for confirmation
new vertica_schema module