Fix bug #505406 - Make thunderbird work on Gentoo again

Changes made:
- Support thunderbird_tmp_t for /tmp created files and directories
- Support XDG types
- Make user content management optional (through access template)
Add description for generated tunables (thunderbird)
Add context for thunderbird (non-bin distro) as per bug #505406
Update file context definition for glsa-check
Mark python-exec/layman as portage_fetch_exec_t
Layman needs manage rights on portage cache (write to /var/cache/edb) as well as ebuild symlinks
Introduce shutdown_dontaudit_exec
Revert last change, not needed
tmpfiles on gentoo needs a few extra perms

currently tmpfiles.sh runs mknod which creates device_t
and is relabelled afterwards.
Allow dhcpc to create and manage control sockets
Moving Gentoo specifics downward
Fix bug #516512 - Support non-root X11 which uses ~/.local/share/xorg
Use logging_search_logs, not logging_search_log

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Use logging_search_logs, not logging_search_log

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Use files_search_etc, not logging_search_etc

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Use files_search_etc, not logging_search_etc

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Use files_search_etc, not files_search_config

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Use corecmd_search_bin, not corecmd_searh_bin

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Use fs_search_tmpfs, not files_search_tmpfs

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Use domain_auto_trans, not auto_trans

Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>