[WIP] Aggsig Transactions (#530)

* First steps converting transaction workflow to be aggsig-enable

* integrating updated version of aggsig, which gives greater control over the contents of e

* added wallet transaction test to testing framework to enable testing the whole thing, completed interaction as far as inital response from recipient

* more aggsig work, final signature is produced now

* Construction of aggsig transaction now working to the point of the signature being built

* aggsig transactions working end-to-end in the nominal case

* refactor aggsig verify from commit and fix some tests

* more cleanup and test fixing

* cleaning up automated tests

* test+formatting fix

pool/src/pool.rs

@@ -737,7 +737,7 @@ mod tests {
    // a valid transaction.
 			let valid_transaction = test_transaction(vec![5, 6], vec![9]);
 
-			match write_pool.add_to_memory_pool(test_source(), valid_transaction) {
+			match write_pool.add_to_memory_pool(test_source(), valid_transaction.clone()) {
 				Ok(_) => {}
 				Err(x) => panic!("Unexpected error while adding a valid transaction: {:?}", x),
 			};
@@ -764,9 +764,15 @@ mod tests {
 				}
 			};
 
-			let already_in_pool = test_transaction(vec![5, 6], vec![9]);
+			// Note, this used to work as expected, but after aggsig implementation
+			// creating another transaction with the same inputs/outputs doesn't create
+			// the same hash ID due to the random nonces in an aggsig. This
+			// will instead throw a (correct as well) Already spent error. An AlreadyInPool
+			// error can only come up in the case of the exact same transaction being
+			// added
+			//let already_in_pool = test_transaction(vec![5, 6], vec![9]);
 
-			match write_pool.add_to_memory_pool(test_source(), already_in_pool) {
+			match write_pool.add_to_memory_pool(test_source(), valid_transaction) {
 				Ok(_) => panic!("Expected error when adding already in pool, got Ok"),
 				Err(x) => {
 					match x {