Show invalid parser as error in the logger

[bosd]

Change logger levels.

1. In case an template specifies no or an invalid parser show it in the logger.

(This is usefull when someone wants to commit an template, pytest on hg actions will show the error).
The user will then be aware that the template needs fixing.

2. In case an invoice file does not return a value, only show a warning.
   In Example coolblue #428 is a template which support multiple invoice layouts. In some cases the website field is not matched. This is intentional. This should only show as a warning in the logger. This is not an error that needs immediate fixing.