Accept both comma and dot as decimal separator

[Vanav]

If I choose locale with comma as decimal separator (e.g. Russian), comma still is not accepted as input.:

Suggestion: please, accept both comma and dot as the same decimal separator in this case. It will be possible to paste numbers from different sources (local with comma or foreign with dot) and always get the correct answer.

OpalCalc do this, and it is very useful:

Related: #13, #7

[bornova]

Hi @Vanav,
This one is a tricky one and I have gone back and forth couple times on this. We removed this feature in v6 because it caused inconsistencies in the user experience (see #112). However, I will keep this issue open and see if there is a good way to implement this to bring it back.

[Vanav]

That is sad to hear. I can accept incorrect tooltips, not a big deal, if parser accepts both separators. Seems that everyone has his own preference, and it is understandable - we work with data sources in different style.

I think best would be to add two settings:
Input: [ ] Accept comma as decimal separator (default disabled)
Output: Decimal separator: dot (default) or comma (dropdown)
By default it is like the current behavior.

If input comma decimal separator is enabled, then both dot and comma are accepted as decimal separator, and function arguments separator is a semicolon.

Output separator defined by setting. It is sometimes useful to switch to copy and paste in documents with different styles.

This is better than pre-v6 behavior, because it is clear and explicit: the issue #112 was that user set the locale, but didn't expected that function arguments separator will change.