Added regex support as per issue #164.

jq now depends on oniguruma for regex support.
Modified configure.ac accordingly.

Added valgrind suppression file for oniguruma to prevent one-time and bounded
leaks from causing tests to fail.

Signed-off-by: Nicolas Williams <nico@cryptonector.com>

tests/run

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 if which valgrind > /dev/null; then
-    VALGRIND='valgrind --error-exitcode=1 -q --leak-check=full'
+    VALGRIND='valgrind --error-exitcode=1 -q --leak-check=full --suppressions=tests/onig.supp'
 else
     VALGRIND=
 fi