Auto merge of #1311 - ebfull:cleanup-pp, r=ebfull

Deallocate the public parameters during Shutdown.

This also has it deallocated in `GenerateParams` and `test_bitcoin`. The virtual destructor probably isn't necessary but I added it just in case we need it some other time.

src/test/test_bitcoin.cpp

@@ -43,6 +43,7 @@ BasicTestingSetup::BasicTestingSetup()
 BasicTestingSetup::~BasicTestingSetup()
 {
         ECC_Stop();
+        delete pzcashParams;
 }
 
 TestingSetup::TestingSetup()