Merged from trunk 5460:5471

Merged from trunk 5460:5471

As a workaround for bug #147625, spawn `id -g portage` in order to get a list of
groups for the portage user without the need to call grp.getgrall().
(prefix uses portage_const.portageuser instead of hardcoded value)

Use -G instead of -g (typo from the previous commit).

Make repoman use portage.normalize_path instead of os.path.normpath.  This might
solve an issue with incorrect repolevel detection that was reported by drizzt.

For python-2.3 compatibility, don't pass an iterable into dict.update().

For bug #160299, make sure that emerge sees a somewhat valid COUNTER even when
the counter is missing.

Fix shell glob logic that leads to false positives.  Thanks to Flameeyes for
reporting.

Fix one more potential false glob match.

revert previous changes ... ruby.eclass is wrongly polluting env with nullglob (SpankMan)

force C locale for now when parsing gcc log files #160234 (SpankMan)

For bug #160310, allow \ inside `` quotes in order to prevent a false Line
continuation ("\") Syntax Error.

For bug #160310, remove the line continuation syntax check since it's still
possible for it to generate false positives.

svn path=/main/branches/prefix/; revision=5476