Create a general hook for subiquity

Users should be able to use "ubuntu-bug subiquity" on a system which was installed with subiquity. The hook should include code like the following which will send the bug to the subiquity project.

            report['CrashDB'] = '''{
               "impl": "launchpad",
               "project": "subiquity",
               "bug_pattern_url": "http://people.canonical.com/~ubuntu-archive/bugpatterns/bugpatterns.xml",
            }'''