Remove {big5,gb2312}han collation data

Remove {big5,gb2312}han collation data

1. {big5,gb2312}han collation data is not used by anybody because they're
useless as a sorting order.

  Add a function to trim_data.sh to remove them from zh.txt

2. Remove remove_unihan.sh and add back unihan rules to coll/{zh,ja,ko}.txt.
In ICU 52, tools/genrb does NOT include unihan collation by default so that 
we don't have to bother to remove it from the rule files.

3. Remove obsolete patch files (locale[23].patch)

4. Add LICENSE file (converted from license.html)

5. Update README.chromium accordingly.

6. Check in the updated data file/assembly files.

The net saving in icudtl.dat is ~ 220kB.


BUG=132145
TEST=icudtl.dat is 10576480
TBR=mark

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=264857

[jungshik at Google, 2014-04-18 21:19:28]

Committed patchset #1 manually as r264857 (presubmit successful).

[Mark Mentovai, 2014-04-18 21:38:46]

LGTM