This changes the error handling in loading ignores slightly:
- There is a new ParseError type that is returned as the error
(somewhere in the chain) when the problem was not an I/O error loading
the file, but some issue with the contents.
- If the file was read successfully but not parsed successfully we still
return the lines read (in addition to nil patterns and a ParseError).
- In the API, if the error IsParseError then we return a successful
HTTP response with the lines and the actual error included in the JSON
object.
- In the GUI, as long as the HTTP call to load the ignores was
successful we can edit the ignores. If there was an error we show this
as a validation error on the dialog.
Also some cleanup on the Javascript side as it for some reason used
jQuery instead of Angular for this editor...