Complete path after ~.

Note this is mostly to discuss as if I understood one of your message on
Twitter, this was not possible without fuzzy completion.

I tried with just this patch and that works great.

Note that unlike IPython that right now does :

    ~/<tab> -> /Full/Path/to/user/home

But with this patch this just complete things correctly without
expanding the tab. And I think not expanding the tab is actually better.

Anyway, open that to better understand the why you were waiting for
fuzzy completion.

jedi/api/file_name.py

@@ -37,6 +37,8 @@ def file_name_completions(evaluator, module_context, start_leaf, string,
     like_name_length = len(os.path.basename(string) + like_name)
 
     addition = _get_string_additions(module_context, start_leaf)
+    if string.startswith('~'):
+        string = os.path.expanduser(string)
     if addition is None:
         return
     string = addition + string