Implement NumericUppercaseCollation

Implement NumericUppercaseCollation

This collation orders text with numbers "naturally", so that
'Foo 1' < 'Foo 2' < 'Foo 12'.

Note that this only works in terms of sequences of digits, and the
behavior for decimal fractions or pretty-formatted numbers may be
unexpected.

This is only expected to work mostly correctly for English-language
text. Consider it a proof of concept. You probably want to use
an UCA collation with '-u-kn' suffix rather than this.

Bug: T8948
Change-Id: Ie268f2d92c5c75d0aaecf54ede2bdda1af3b309d