Add comma support for weight input

[christirichards]

We've received a few reports of users not being able to use a comma in place of a decimal point. See below:

"I live in Sweden and my keyboard is set up to use a comma (,) when writing a decimal point - e.g. when documenting my weight, my numeric keyboard only allows me to separate fractions of a kilogram with a comma. i.e. 85,1 kg instead of 85.1 kg. Unfortunately, the app won’t register the comma! I have just discovered this today."

[marc-medley]

Note: regional number support ties into data entry, HealthKit sync, database normalized form and import/export.

This issue also has a dimension where the user can select the number format region separate to the different from the typical selected app language region.

Status: a cohesive solution regional number representation for data imput, HealthKit sync, database normalized form and import/export has been implemented and checked in. The stored data is normalized to a binary kg Double. Unit tests have between added to verify correct function of the solutioned as languages and regions are added.

Next step is to complete testing and release.