Implemented automatic PUT/PATCH detection

When using POST /arbitrary/{service}/{name}... it will now automatically decide which method to use (PUT/PATCH) based on a few factors:

- If there are already 10 or more layers, use PUT to reset back to a single layer
- If the next layer's patch is more than 20% of the total resource file size, use PUT
- If the next layer modifies more than 50% of the total file count, use PUT
- Otherwise, use PATCH

The PUT method causes a new base layer to be created and all previous update history for that resource becomes obsolete. The PATCH method adds a small delta layer on top of the existing layer(s).

The idea is to wipe the slate clean with a new base layer once the patches start to get demanding for the network to apply. Nodes which view the content will ultimately have build timeouts to prevent someone from deploying a resource with hundreds of complex layers for example, so this approach is there to maximize the chances of the resource being buildable.

The constants above (10 layers, 20% total size, 50% file count) will most likely need tweaking once we have some real world data.

src/test/java/org/qortal/test/arbitrary/ArbitraryDataTests.java

@@ -370,7 +370,8 @@ public class ArbitraryDataTests extends Common {
         ArbitraryDataTransactionBuilder txnBuilder = new ArbitraryDataTransactionBuilder(
                 publicKey58, path, name, method, service, identifier);
 
-        ArbitraryTransactionData transactionData = txnBuilder.build();
+        txnBuilder.build();
+        ArbitraryTransactionData transactionData = txnBuilder.getArbitraryTransactionData();
         Transaction.ValidationResult result = TransactionUtils.signAndImport(repository, transactionData, account);
         assertEquals(Transaction.ValidationResult.OK, result);
         BlockUtils.mintBlock(repository);