Integrate SFMT 1.3.3 into test infrastructure.

Integrate the SIMD-oriented Fast Mersenne Twister (SFMT) 1.3.3 into the
test infrastructure.

The sfmt_t state encapsulation modification comes from Crux
(http://www.canonware.com/Crux/) and enables multiple
concurrent PRNGs.

test/unit/SFMT.c is an adaptation of SFMT's test.c that performs all the
same validation, both for 32- and 64-bit generation.

.gitignore

@@ -39,6 +39,7 @@
 
 /test/test.sh
 test/include/test/jemalloc_test.h
+test/include/test/jemalloc_test_defs.h
 
 /test/integration/[A-Za-z]*
 !/test/integration/[A-Za-z]*.*