fix various property issues

property cleanup

Make dependency generation work on OS/2. The preprocessor outputs \\'s as path separators so switch them to /'s

These changes are committed together, because they depend on each other. - shared modules can be built in the tree - added support for --with-layout, uses APACI's config.layout - working 'make install' - working 'make depend' - working Pthreads checks - buildconf replaced