Adding a C test demonstrating that our build of GMP leaks memory.
Okay, NOW it links against our GMP library.  Sheesh

Needed to send -L(library path) in on the compopts line and make sure our
environment for compilation included LD_LIBRARY_PATH being expanded to contain
it as well.
Add a future and skipif for the C test, and skip the original for valgrind

Log the failure behavior on the C test and only run it with valgrind enabled.
Also, skip the original test for valgrind until this future has been resolved.
Glarble blarble whitespace blurble glurble
Take Vass's comment into account.
Merge pull request #774 from lydia-duncan/gmpLeakCTest

Gmp leak c test [reviewed by Vass]

Add a future to demonstrate the leak of memory from our GMP build,
as discovered in test/modules/standard/gmp/ferguson/gmp_dist_array.
Turned off that test for valgrind until this issue has been resolved.