Reorganize script_util
Reorganize script_util

Organize scripts by chapter in The Unicode Standard. Add Brahmi script.
Tweak progress reporting.

google/language-resources,googlei18n/language-resources,google/language-resources,google/language-resources,google/language-resources,google/language-resources,googlei18n/language-resources,googlei18n/language-resources,googlei18n/language-resources,google/language-resources,googlei18n/language-resources,googlei18n/language-resources