Schema fixes/clarifications that came up working on codegen (#196)

Author: tetron

Process.yml

@@ -759,7 +759,11 @@ $graph:
   extends: [Parameter, InputFormat, LoadContents]
   fields:
     - name: default
-      type: Any?
+      type:
+        - "null"
+        - File
+        - Directory
+        - Any
       jsonldPredicate:
         _id: sld:default
         noLinkCheck: true
@@ -852,7 +856,10 @@ $graph:
         error and the implementation must not attempt to run the process,
         unless overridden at user option.
     - name: hints
-      type: Any[]?
+      type:
+        - "null"
+        - type: array
+          items: [ProcessRequirement, Any]
       doc: |
         Declares hints applying to either the runtime environment or the
         workflow engine that may be helpful in executing this process.  It is

Workflow.yml

@@ -225,15 +225,15 @@ $graph:
   fields:
     - name: outputSource
       doc: |
-        Specifies one or more names of an output from a workflow step (in the form 
+        Specifies one or more names of an output from a workflow step (in the form
         `step_name/output_name` with a `/` separator`), or a workflow input name,
         that supply their value(s) to the output parameter.
         the output parameter.  It is valid to reference workflow level inputs
         here.
       jsonldPredicate:
         "_id": "cwl:outputSource"
         "_type": "@id"
-        refScope: 0
+        refScope: 1
       type:
         - string?
         - string[]?