PR Checklist

• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/tools/notes/CONTRIBUTING.md#commit-messages.
• There is an issue for the bug/feature this PR is for. To avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it.
• You have signed the CLA.
• All existing tests are passing: https://github.com/NativeScript/NativeScript/blob/master/tools/notes/DevelopmentWorkflow.md#running-unit-tests-application.
• Tests for the changes are included - https://github.com/NativeScript/NativeScript/blob/master/tools/notes/WritingUnitTests.md.

What is the current behavior?

Right now, CSS text-transform property does not respect locale.
This results in incorrect text casing for languages other than English.

What is the new behavior?

CSS text-transform property will respect current locale (can be changed using native apis).
This PR also contains a new and accurate capitalization function to ensure capitalize is identical in both platforms (inspired by Apache WordUtils.capitalize).

Users can also use @nativescript/localize or @nativescript-community/l plugins to switch locale to one of their own and text-transform will respect that.
For @nativescript/localize, use overrideLocale and androidLaunchEventLocalizationHandler functions.
For @nativescript-community/l, use overrideNativeLocale function.