BHV-3181: Add method for determining RTL mode based on first character of string content.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>
ENYO-3181: Generalize text directionality check as a utility function, use regular expressions instead of range checks.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>
BHV-3181: Remove astral range from regex pattern.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>
BHV-3181: Remove string conversion of array as regex handles this.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>
Merge pull request #699 from enyojs/BHV-3181-aarontam-RC

BHV-3181: Add method for determining RTL mode based on string content. (RC)
Update version string to 2.3.0-rc.18