Fix/remove limit with format_exc_skip

This used limit=5 in several places, but this limits it to the first 5
frames, hiding the source of the exception!

While limit=-5 could be used instead, I think it is better to provide
the full traceback always.

neovim/api/nvim.py

@@ -159,7 +159,7 @@ def filter_request_cb(name, args):
                 result = request_cb(name, args)
             except Exception:
                 msg = ("error caught in request handler '{} {}'\n{}\n\n"
-                       .format(name, args, format_exc_skip(1, 5)))
+                       .format(name, args, format_exc_skip(1)))
                 self._err_cb(msg)
                 raise
             return walk(self._to_nvim, result)
@@ -171,7 +171,7 @@ def filter_notification_cb(name, args):
                 notification_cb(name, args)
             except Exception:
                 msg = ("error caught in notification handler '{} {}'\n{}\n\n"
-                       .format(name, args, format_exc_skip(1, 5)))
+                       .format(name, args, format_exc_skip(1)))
                 self._err_cb(msg)
                 raise
 
@@ -342,7 +342,7 @@ def handler():
             except Exception as err:
                 msg = ("error caught while executing async callback:\n"
                        "{!r}\n{}\n \nthe call was requested at\n{}"
-                       .format(err, format_exc_skip(1, 5), call_point))
+                       .format(err, format_exc_skip(1), call_point))
                 self._err_cb(msg)
                 raise
         self._session.threadsafe_call(handler)

neovim/plugin/host.py

@@ -71,11 +71,11 @@ def _wrap_function(self, fn, sync, decode, nvim_bind, name, *args):
         except Exception:
             if sync:
                 msg = ("error caught in request handler '{} {}':\n{}"
-                       .format(name, args, format_exc_skip(1, 5)))
+                       .format(name, args, format_exc_skip(1)))
                 raise ErrorResponse(msg)
             else:
                 msg = ("error caught in async handler '{} {}'\n{}\n"
-                       .format(name, args, format_exc_skip(1, 5)))
+                       .format(name, args, format_exc_skip(1)))
                 self._on_async_err(msg + "\n")
 
     def _on_request(self, name, args):