Commands/Create: Adds support for creating workloads

The create command can now be used to create workloads for the various
types.

wa/commands/templates/apk_workload

@@ -0,0 +1,54 @@
+from wa import Parameter, ApkWorkload
+
+
+class ${class_name}(ApkWorkload):
+
+    name = '${name}'
+    description = "This is an placeholder description"
+    # Replace with a list of supported package name(s) in the APK file(s).
+    package_names = ['package_name']
+
+    parameters = [
+        # Workload parameters go here e.g.
+        Parameter('example_parameter', kind=int, allowed_values=[1,2,3],
+                  default=1, override=True, mandatory=False,
+                  description='This is an example parameter')
+    ]
+
+    def __init__(self, target, **kwargs):
+        super(${class_name}, self).__init__(target, **kwargs)
+        # Define any additional attiributes required for the workload
+
+    def init_resources(self, context):
+        super(${class_name}, self).init_resources(context)
+        # This method may be used to perform early resource discovery and
+        # initialization. This is invoked during the initial loading stage and
+        # before the device is ready, so cannot be used for any device-dependent
+        # initialization. This method is invoked before the workload instance is
+        # validated.
+
+    def initialize(self, context):
+        super(${class_name}, self).initialize(context)
+        # This method should be used to perform once-per-run initialization of a
+        # workload instance.
+
+    def validate(self):
+        super(${class_name}, self).validate(context)
+        # Validate inter-parameter assumptions etc
+
+    def setup(self, context):
+        super(${class_name}, self).setup(context)
+        # Perform any necessary setup before starting the application
+
+    def extract_results(self, context):
+        super(${class_name}, self).extract_results(context)
+        # Extract results on the target
+
+    def update_output(self, context):
+        super(${class_name}, self).update_output(context)
+        # Update the output within the specified execution context with the
+        # metrics and artifacts form this workload iteration.
+
+    def teardown(self, context):
+        super(${class_name}, self).teardown(context)
+        # Perform any final clean up for the Workload.