builld: allow out of source build * Makefile.in: add TOP_BUILD_DIR var and use TOP_DIR=srcdir, TOP_BUILD_DIR=builddir, modify paths to use TOP_DIR where needed * binary-dist-rules.mk: use TOP_DIR and TOP_BUILD_DIR where needed * makeinst-script.sh: use script path to determine TOPDIR, use TOPDIR where needed * src/default-octave.mk: install octave-version to builddir * src/stable-octave.mk: install octave-version to builddir * src/octave.mk: install octave-version to builddir * tools/set-mxe-env.sh.in: update fir builddir and srcdir use

--- librsb-1.2.0-rc2/rsb_sys.h.orig	2015-11-08 08:20:56.737959489 -0500
+++ librsb-1.2.0-rc2/rsb_sys.h	2015-11-08 08:24:46.712072656 -0500
@@ -204,6 +204,8 @@
 
 #ifdef RSB_HAVE_BZERO
 #define RSB_BZERO bzero		/**< we have the chance of using a custom bzero function in this way */
+#elif RSB_HAVE_MEMSET 
+#define RSB_BZERO(a,b) memset(a,0,b)
 #else /* RSB_HAVE_BZERO */
 #error "missing a definition of RSB_BZERO!"
 #endif /* RSB_HAVE_BZERO */