Use nomad meta info package instead of weird relative paths.

common/python/nomadcore/local_meta_info.py

@@ -668,7 +668,8 @@ def load_metainfo(filename, dependencyLoader=None, extraArgsHandling=InfoKindEl.
         Tuple containing the metainfo environment, and any possible warnings
         that were encountered in the loading.
     """
-    path = os.path.normpath(os.path.join(os.path.dirname(os.path.abspath(__file__)), "../../../../nomad-meta-info/meta_info/nomad_meta_info/{}".format(filename)))
+    import nomad_meta_info
+    path = os.path.normpath(os.path.join(os.path.dirname(os.path.abspath(nomad_meta_info.__file__)), "{}".format(filename)))
     return loadJsonFile(path, dependencyLoader, extraArgsHandling, uri)
 
 def loadJsonStream(fileStream, name = None, dependencyLoader = None, extraArgsHandling = InfoKindEl.ADD_EXTRA_ARGS, filePath = None, uri = None):