checks for the existence of glibtool using hash rather than testing f…

…or the hardcoded path /usr/bin/glibtool. This ensures that glibtool and glibtoolize that are not located in /usr/bin (e.g. /usr/local/bin) can be found as long as their root folder is contained in the $PATH environment variable.

autogen.sh

@@ -29,7 +29,8 @@ test -z "$AUTOMAKE" && AUTOMAKE=automake
 test -z "$ACLOCAL" && ACLOCAL=aclocal
 test -z "$AUTOCONF" && AUTOCONF=autoconf
 test -z "$AUTOHEADER" && AUTOHEADER=autoheader
-if [ -x /usr/bin/glibtool ]; then
+
+if hash glibtool 2>&-; then
  test -z "$LIBTOOL" && LIBTOOL=glibtool
  test -z "$LIBTOOLIZE" && LIBTOOLIZE=glibtoolize
 else