Add request source

Add "request" source with support for "method" and "remote-addr"
parameters.  Both values are taken from the raw http.Request object.

Fixes #312

test/hooks.json.tmpl

@@ -252,6 +252,21 @@
     "include-command-output-in-response": true,
     "include-command-output-in-response-on-error": true
   },
+  {
+    "id": "request-source",
+    "pass-arguments-to-command": [
+      {
+        "source": "request",
+        "name": "method"
+      },
+      {
+        "source": "request",
+        "name": "remote-addr"
+      }
+    ],
+    "execute-command": "{{ .Hookecho }}",
+    "include-command-output-in-response": true
+  },
   {
     "id": "static-params-ok",
 		"execute-command": "{{ .Hookecho }}",

test/hooks.yaml.tmpl

@@ -152,6 +152,15 @@
   include-command-output-in-response: true
   include-command-output-in-response-on-error: true
 
+- id: request-source
+  pass-arguments-to-command:
+  - source: request
+    name: method
+  - source: request
+    name: remote-addr
+  execute-command: '{{ .Hookecho }}'
+  include-command-output-in-response: true
+
 - id: static-params-ok
   execute-command: '{{ .Hookecho }}'
   include-command-output-in-response: true