Split each benchmark into its own directory ... again.

Turns out that merging similar benchmarks into a single directory was
not a good idea.  This patch separates them again, but keeps the source
common.

All similar benchmarks now have different names, and the source lives in
a common central location, so, for example, we have benchmarks
`ctl-stack' and `ctl-vector', and the source for both lives in the `ctl'
directory.

ChangeLog:

	* configure.ac: Add split benchmarks to benchmark list.
	* configure: Regenerate.
	* src/ctl-stack/Makefile.am: New file.
	* src/ctl-stack/Makefile.in: New file.
	* src/ctl-vector/Makefile.am: New file.
	* src/ctl-vector/Makefile.in: New file.
	* src/ctl/Makefile.in: Removed.
	* src/ctl/Makefile.am: Removed.
	* src/matmult-float/Makefile.am: New file.
	* src/matmult-float/Makefile.in: New file.
	* src/matmult-int/Makefile.am: New file.
	* src/matmult-int/Makefile.in: New file.
	* src/matmult/Makefile.am: Removed.
	* src/matmult/Makefile.in: Removed.
	* src/sglib-arrayheapsort/Makefile.am: New file.
	* src/sglib-arrayheapsort/Makefile.in: New file.
	* src/sglib-arrayquicksort/Makefile.am: New file.
	* src/sglib-arrayquicksort/Makefile.in: New file.
	* src/sglib-arraysort/Makefile.in: Removed.
	* src/sglib-arraysort/Makefile.am: Removed.
	* src/trio-snprintf/Makefile.am: New file.
	* src/trio-snprintf/Makefile.in: New file.
	* src/trio-sscanf/Makefile.am: New file.
	* src/trio-sscanf/Makefile.in: New file.
	* src/trio/Makefile.in: Removed.
	* src/trio/Makefile.am: Removed.