The following steps were taken:

- The icu/ directory was wiped.
- The new version was decompressed in its place.
- The directories source/common/ and source/i18n were git-added.
- Had to change permissions on some files.
- All changed files were added (git add -u.)
- Put back the CMakeLists.txt.
- Updated the CMakeLists.txt files with the current source files.

Change-Id: I47fb3fa0d59e8ecbb76c40051fda0f1c531b923f