Factor out PROJECT_PATH

[benjaoming]

The notion of PROJECT_PATH was tied to the old one-dimensional single-dir-based distribution where the kalite package was in limbo between being a django app and a django project.

It didn't really make itself understandable, neither, because the project was either the top-most level / or the /kalite/ dir.

Everywhere that PROJECT_PATH is used, it reveals some level of implicit structure. We need to go through all the occurrences and replace them with the new settings strategy #4054

On a secondary note, PROJECT_PATH was actually never a "setting", it was never supposed to be changed.

✗ ack-grep --python PROJECT_PATH kalite

kalite/playlist/management/commands/checkplaylistentries.py
22:        all_playlists = json.load(open(os.path.join(settings.PROJECT_PATH, 'playlist/playlists.json')))

kalite/basetests/tests.py
6:PROJECT_PATH = os.path.realpath(os.path.join(THIS_PATH, "..", ".."))
11:        os.path.join(PROJECT_PATH),
12:        os.path.join(PROJECT_PATH, "kalite"),
13:        os.path.join(PROJECT_PATH, "python-packages"),
315:        content_path = os.path.realpath(os.path.join(PROJECT_PATH, "content"))
320:        khan_path = os.path.realpath(os.path.join(PROJECT_PATH, "data", "khan"))
325:        khan_path = os.path.realpath(os.path.join(PROJECT_PATH, "data", "khan"))
351:        scripts_path = os.path.realpath(os.path.join(PROJECT_PATH, "scripts"))

kalite/distributed/management/commands/apacheconfig.py
34:            "project_path": settings.PROJECT_PATH,

kalite/distributed/management/commands/nginxconfig.py
76:        self.stdout.write(config_template % {"root_path": os.path.realpath(settings.PROJECT_PATH + "/../"),

kalite/distributed/management/commands/setup.py
359:        # call_command("clean_pyc", interactive=False, verbosity=options.get("verbosity"), path=os.path.join(settings.PROJECT_PATH, ".."))
468:                        os.path.join(settings.PROJECT_PATH, "..", "bin", kalite_executable))
471:                        os.path.join(settings.PROJECT_PATH, "..", "bin", "windows", "kalite.bat"))

kalite/distributed/management/commands/screenshots.py
184:            self.output_path = os.path.join( os.path.realpath(os.path.join(settings.PROJECT_PATH, '..')),

kalite/distributed/management/commands/initdconfig.py
84:            executable_path = os.path.abspath(os.path.join(settings.PROJECT_PATH, "..", "bin", "kalite"))
85:            cwd = settings.PROJECT_PATH

[benjaoming]

Fixed in #5429