yat_m4_test.sh does not honor --prefix and friend set at make time

[Peter]

yat_m4_test.sh is built at configure time and thus does not depend on flags set at make time. For instance,

./configure
make clean
make prefix=/tmp
make install
make installcheck

will fail because prefix in yat_m4_test.sh is set to /usr/local.

[Peter]

closed in r1769

The test of YAT_CHECK_YAT macro is modified so it handles a sequence like: ./configure && make check && make prefix=my_prefix && make install prefix=my_prefix && make installcheck prefix=my_prefix

added a test in maintainer-check that checks this ( I know... testing tests)

Still, there are may situations in which installcheck fails, e.g., when using DESTDIR, so I the test is only tunred on in enable-svn-support mode. Before it was turned on if autotools were available and since we don't need the information whether autotools are available, I removed the configure tests for that.

fixes #486

[Peter]

(In [1770]) In maintainer-check in yat_test_yat was not run since configure was run without --enable-svn-support; and it can't since it not a svn wc (but svn exported).

Because of this, I now call yat_check_yat_test.sh explicitly and removed the the test from installcheck-local.

refs #486