Remove need to edit trigger when creating new workflow

[martyychang]

Right now, when creating a new trigger workflow, the developer has to do the following.

1. Create the workflow class
2. Edit the appropriate trigger
3. Create the custom metadata record

However, since the Type class supports a Type.forName(String) method which can be used to dynamically construct a Type object which can then be used to get an instance of that type, it would be great if the developer can simply do the following.

1. Create the workflow class
2. Create the custom metadata record

The trigger should simply need to be created once, with custom metadata determining whether a workflow is executed and in what order.

[martyychang]

As part of #11 it was trivial to add an additional ORDER BY clause to the query used to return active workflows for a given object. If the change passes deployment and testing in a sandbox, this issue will also be resolved as a byproduct.