added basic tests around range_proof (#121)

Pass nonce in to range_proof (we need it for rewind_range_proof, at least for testing)

pool/src/graph.rs

@@ -233,7 +233,7 @@ mod tests {
         let outputs = vec![core::transaction::Output{
                 features: core::transaction::DEFAULT_OUTPUT,
                 commit: output_commit,
-                proof: ec.range_proof(0, 100, key::ZERO_KEY, output_commit)}];
+                proof: ec.range_proof(0, 100, key::ZERO_KEY, output_commit, ec.nonce())}];
         let test_transaction = core::transaction::Transaction::new(inputs,
             outputs, 5);
 

pool/src/pool.rs

@@ -892,7 +892,7 @@ mod tests {
         transaction::Output{
             features: transaction::DEFAULT_OUTPUT,
             commit: output_commitment,
-            proof: ec.range_proof(0, value, output_key, output_commitment)}
+            proof: ec.range_proof(0, value, output_key, output_commitment, ec.nonce())}
     }
 
     /// Makes a SecretKey from a single u64