[license] start to document license.conf

- document keys and values in a way consistent with other modules
 - document **intended** use of local URLs.

src/modules/license/license.conf

@@ -1,14 +1,26 @@
 # Configuration file for License viewmodule, Calamares
 # Syntax is YAML 1.2
 ---
-# YAML: list of maps.
+# Define a list of licenses which may / must be accepted before continuing.
+#
+# Each entry in this list has the following keys:
+#   - id        Entry identifier, must be unique. Not user visible. YAML: string.
+#   - name      Pretty name for the software product, user visible and untranslatable. YAML: string.
+#   - vendor    Pretty name for the software vendor, user visible and untranslatable. YAML: string, optional, default is empty.
+#   - type      Package type identifier for presentation, not user visible but affects user visible strings. YAML: string.
+#               values: driver, gpudriver, browserplugin, codec, package, software; optional, default is software.
+#   - required  If set to true, the user cannot proceed without accepting this license. YAML: boolean, optional, default is false.
+#   - url       A URL for the license; a remote URL is not shown in Calamares, but a link
+#               to the URL is provided, which opens in the default web browser. A local
+#               URL (i.e. file:///) assumes that the contents are HTML or plain text, and
+#               displays the license in-line. YAML: string, mandatory.
 entries:
-- id:       nvidia      # Entry identifier, must be unique. Not user visible. YAML: string.
-  name:     Nvidia      # Pretty name for the software product, user visible and untranslatable. YAML: string.
-  vendor:   Nvidia Corporation # Pretty name for the software vendor, user visible and untranslatable. YAML: string, optional, default is empty.
-  type:     driver      # Package type for presentation, not user visible but affects user visible strings. YAML: string, allowed values: driver, gpudriver, browserplugin, codec, package, software; optional, default is software.
-  url:      http://developer.download.nvidia.com/cg/Cg_3.0/license.pdf  # Url of license text to display in a web view. YAML: string.
-  required: false       # If set to true, the user cannot proceed without accepting this license. YAML: boolean, optional, default is false.
+- id:       nvidia
+  name:     Nvidia
+  vendor:   Nvidia Corporation
+  type:     driver
+  url:      http://developer.download.nvidia.com/cg/Cg_3.0/license.pdf
+  required: false
 - id:       amd
   name:     Catalyst
   vendor:   "Advanced Micro Devices, Inc."