Add --without-isam configure switch.

Portability fix for mysqlmanager.


acconfig.h:
  Add HAVE_ISAM
acinclude.m4:
  Add --without-isam configure switch.
configure.in:
  Add --without-isam configure switch.
include/my_global.h:
  remove #define HAVE_ISAM
libmysqld/examples/test-run:
  pass --language option to embedded server
sql/Makefile.am:
  use @isam_libs@ instead of hard-coded values
tools/mysqlmanager.c:
  #include <signal.h> for portability

acinclude.m4

@@ -814,6 +814,23 @@ AC_SUBST(orbit_libs)
 AC_SUBST(orbit_idl)
 ])
 
+AC_DEFUN([MYSQL_CHECK_ISAM], [
+  AC_ARG_WITH([isam], [\
+  --without-isam          Disable the ISAM table type],
+    [with_isam="$withval"],
+    [with_isam=yes])
+
+  isam_libs=
+  if test X"$with_isam" = X"yes"
+  then
+    AC_DEFINE(HAVE_ISAM)
+    isam_libs="\$(top_builddir)/isam/libnisam.a\
+ \$(top_builddir)/merge/libmerge.a"
+  fi
+  AC_SUBST(isam_libs)
+])
+
+
 dnl ---------------------------------------------------------------------------
 dnl Macro: MYSQL_CHECK_BDB
 dnl Sets HAVE_BERKELEY_DB if inst library is found