portage-conf: Move package.keywords to package.accept_keywords

This brings me up to date with Portage's 39020a6 (Add support for
/etc/portage/package.accept_keywords, 2010-08-15) [1].

Thanks to Chí-Thanh Christopher Nguyễn (chithead) and Ben Kohler
(iamben) for pointing this out to me on #gentoo.

[1]: http://git.overlays.gentoo.org/gitweb/?p=proj/portage.git;a=commit;h=39020a6a418c0910b372e04a8f4959ce258d1989

diff --git a/portage-conf/default/package.keywords/bugs b/portage-conf/default/package.accept_keywords/bugs
similarity index 100%
rename from portage-conf/default/package.keywords/bugs
rename to portage-conf/default/package.accept_keywords/bugs

diff --git a/portage-conf/default/package.keywords/hdf5 b/portage-conf/default/package.accept_keywords/hdf5
similarity index 100%
rename from portage-conf/default/package.keywords/hdf5
rename to portage-conf/default/package.accept_keywords/hdf5

diff --git a/portage-conf/default/package.keywords/ipython b/portage-conf/default/package.accept_keywords/ipython
similarity index 100%
rename from portage-conf/default/package.keywords/ipython
rename to portage-conf/default/package.accept_keywords/ipython

diff --git a/portage-conf/default/package.keywords/matplotlib b/portage-conf/default/package.accept_keywords/matplotlib
similarity index 100%
rename from portage-conf/default/package.keywords/matplotlib
rename to portage-conf/default/package.accept_keywords/matplotlib

diff --git a/portage-conf/default/package.keywords/mayavi b/portage-conf/default/package.accept_keywords/mayavi
similarity index 100%
rename from portage-conf/default/package.keywords/mayavi
rename to portage-conf/default/package.accept_keywords/mayavi

diff --git a/portage-conf/default/package.keywords/networkx b/portage-conf/default/package.accept_keywords/networkx
similarity index 100%
rename from portage-conf/default/package.keywords/networkx
rename to portage-conf/default/package.accept_keywords/networkx

diff --git a/portage-conf/default/package.keywords/pandas b/portage-conf/default/package.accept_keywords/pandas
similarity index 100%
rename from portage-conf/default/package.keywords/pandas
rename to portage-conf/default/package.accept_keywords/pandas

diff --git a/portage-conf/default/package.keywords/sympy b/portage-conf/default/package.accept_keywords/sympy
similarity index 100%
rename from portage-conf/default/package.keywords/sympy
rename to portage-conf/default/package.accept_keywords/sympy

diff --git a/portage-conf/default/package.keywords/x b/portage-conf/default/package.accept_keywords/x
similarity index 100%
rename from portage-conf/default/package.keywords/x
rename to portage-conf/default/package.accept_keywords/x