evas textblock: add align=locale option to respect locale's direction

evas textblock: add align=locale option to respect locale's direction

Summary:
There are many requests to add a new feature for handling horizontal align
according to current locale. For example, in RTL locale setting,
users want to see right aligned text for every list's item.
Even if some of list's items only contain LTR characters!
It is useful for the needs.
@feature

Test Plan: N/A

Reviewers: herdsman, tasn, woohyun, raster, cedric

Reviewed By: herdsman, raster

Subscribers: z-wony, jpeg

Differential Revision: https://phab.enlightenment.org/D4664

Change-Id: I23cff606706d421e1f5388875b4062ce112d2e2e