Major cleanup and fixage for new metadata stuff and heckformat

- Clean up a ton of documentation.
- Make the modules import nicely.
- Add a cool logo to the command line tool
- Make the command-line tool use tqdm
- Make the command line tool load the metadata before processing the
  files in a separate loop.
- Fix error handling in the command-line tool processing loops so they
  work correctly (and jinja errors are more useful)
- Make command-line tool exit non-zero if there were errors.
- Fix load metadata to handle formats and errors better (and return {}
  if it fails)

heckweasel/metadata.py

@@ -108,26 +108,28 @@ class MetaTree:
 
     def _load_metadata(self, cachekey: str) -> Dict:
         meta = {}
-        with open(cachekey, "r") as inf:
-            if cachekey.endswith(".heck"):
-                # raise NotImplemented("We don't yet support HECKformat")
-                with open(cachekey) as cachefile:
-                    h = heckformat.parse.load(cachefile)
-                    meta = h.flatten_replace()
-            else:
-                try:
-                    # try json load
-                    meta = jstyleson.load(inf)
-                except jstyleson.JSONDecodeError as exc:
-                    # try yaml load
+        try:
+            with open(cachekey, "r") as inf:
+                if cachekey.endswith(".heck"):
+                    with open(cachekey) as cachefile:
+                        h = heckformat.parse.load(cachefile)
+                        meta = h.flatten_replace()
+                else:
                     try:
-                        meta = yaml.load(inf)
-                    except yaml.parser.ParserError as exc2:
-                        # else either the yaml or json has an error
-                        me = MetaLoadError()
-                        exc2.__context__ = exc
-                        raise me from exc2
-            return meta
+                        # try json load
+                        meta = jstyleson.load(inf)
+                    except jstyleson.JSONDecodeError as exc:
+                        # try yaml load
+                        try:
+                            meta = yaml.load(inf)
+                        except yaml.parser.ParserError as exc2:
+                            # else either the yaml or json has an error
+                            me = MetaLoadError()
+                            exc2.__context__ = exc
+        except BaseException as inst:
+            logger.error(f"Can't load any metadata for key {cachekey}: {inst}")
+
+        return meta
 
     def get_metadata(self, rel_path: str) -> Dict:
         """Retrieve the metadata for a given path