[MERGE] SourceLayout: src/auth and src/fs, takes 0

Hello,

    This merge bundle makes "make distclean" work in my tests. Most
changes were SourceLayout-related and affected two directories: src/auth
and src/fs. Both directories need more work to complete their layout
polishing, but the current changes are the step in the right direction,
IMO. Details are below.

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SourceLayout: src/auth, take 0

Moved src/AuthFoo* to src/auth/Foo*

Simplified and documented AUTH_* autotools variables.
All auth libraries are built in auth/ now.
Auth sources are no longer added to executables directly.

TODO: Add Makefiles to specific auth modules.
TODO: Add Auth namespace and rename auth classes accordingnly.

These changes were triggered by "make distclean" work.

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SourceLayout: src/fs, take 0

Simplified and documented STORE_* autotools variables.
All fs code is built as fs/lib*.a libraries now, no exception for
diskd and aufs "fake" legacy modules.
fs/* sources are no longer added to executables directly.

TODO: Add Makefiles to specific fs modules.
TODO: Add Fs namespace and rename fs classes accordingly.

testHeaders in fs/Makefile.am requires absolute source directories for
out-of-tree checks to work.

Removed src/ip/stubQosConfig.cc from STORE_TEST_SOURCES. It does not
seem to be needed in my tests. If it is needed, the stub file should be
moved into src/tests to avoid dependency on a source in a directory with
a Makefile. If the stub is not needed at all, it should be removed from
the tree. Note that src/ip/stubQosConfig.cc is non-empty only when
--enable-zph-qos.

These changes were triggered by "make distclean" work.
---------------

Please test and yell if you find any problems in your environment.

Thank you,

Alex.
bb:approve