[license] Update example

- Explain that the GPLv3 isn't actually a proprietary license, but
   is used as convenient text for the license page.
 - Invent a Calamares, Inc.

src/modules/license/license.conf

@@ -33,9 +33,13 @@ entries:
   type:     browserplugin
   url:      http://www.adobe.com/products/eulas/pdfs/PlatformClients_PC_WWEULA_Combined_20100108_1657.pdf
   required: true
-- id:   gpl
-  name: GNU General Public License v3
-  vendor: FSF
-  type: erp
+# This example uses a file: link. This example uses a relative link, which
+# is relative to where you run Calamares. Assuming you run it from build/
+# as part of your testing, you'll get the LICENSE text for Calamares
+# (which is the text of the GPLv3, not proprietary at all).
+- id:   mine_mine
+  name: Calamares Proprietary License
+  vendor: Calamares, Inc.
+  type: software
   required: true
-  url: file:///tmp/COPYING.txt
+  url: file:../LICENSE