Windows support

Lexicons.py

@@ -363,7 +363,7 @@ def KnownLexicons(Directories: list[Path]) -> list[Path]:
 def NewSharedLexicon(Name: str) -> Path:
     """An empty Lexicon in Lexicons/ for other Lexicons to inherit from."""
     Name = Name.strip().removesuffix(".toml")
-    if not Name or "/" in Name or Name.startswith("."):
+    if not Name or "/" in Name or "\\" in Name or Name.startswith("."):
         raise DataError("That isn't a valid file name.")
     LexiconsDir.mkdir(parents=True, exist_ok=True)
     FilePath = LexiconsDir / f"{Name}.toml"