Bug #265747 - Add a new /etc/portage/repos.conf config file which can be used

Bug #265747 - Add a new /etc/portage/repos.conf config file which can be used
to configure site-specific eclass override behavior. Note that configuration
settings which are specified here do not apply to tools such as repoman(1)
and egencache(1) since their operations are inherently not site-specific.
Beware that use of eclass-overrides is generally not recommended and that it
may trigger performance issues under some circumstances (see bug #124041).

Example:

# make all repositories inherit eclasses from the java-overlay and
# java-experimental repositories, with eclasses from java-experimental
# taking precedence over those from java-overlay
[DEFAULT]
eclass-overrides = java-overlay java-experimental

# disable all eclass overrides for the gentoo repository
[gentoo]
eclass-overrides =

svn path=/main/trunk/; revision=13325