lib-dict-backend: Fix linking test-dict-sql dict_drivers_register_builtin() wasn't found.

global: Use check-local in Makefile.am instead of overriding check directly This helps with dependency problems, like running "make check" in lib-storage without "make" first would try to compile the test programs too early and fail.

dict-ldap: Link directly to dict binary, unless --with-ldap=plugin was used This is similar to how authdb_ldap plugin is built.

dict-ldap: Move from plugins/dict-ldap to lib-dict-backend

lib-dict-backend: Build test-dict-sql even without "make check" There's no longer a dependency problem.

lib-dict: Move libdict_backend to lib-dict-backend