added option to remove clozes in frozen fields

[geldbogen]

Description

Added an option to automatically delete the cloze-prompts (i.e. "{{c1::" and "}}") upon creating a new note.

Why is this useful?

Imagine you want to cloze the following information:

If you create the cloze like this:

You will face the following problem:

Here, the information, that she won an Oscar, already hints that she is an actor. So, what do you do instead?

Create multiple clozes in the following manner:

and

Checklist:

Please replace the space inside the brackets with an x and fill out the ellipses if the following items apply:

• [x] I've read and understood the contribution guidelines
• [x] I've tested my changes against at least one of the following Anki builds:
  • [x] Latest standard Anki 2.1 binary build
  • [ ] Latest alternative Anki 2.1 binary build
• [x] I've tested my changes on at least one of the following platforms:
  • [ ] Linux, version:
  • [x] Windows, version:
  • [ ] macOS, version:
• [ ] My changes potentially affect non-desktop platforms, of which I've tested:
  • [ ] AnkiMobile, version:
  • [ ] AnkiDroid, version:
  • [ ] AnkiWeb