Experimental ooRexx5

Forked from https://sourceforge.net/p/oorexx/code-0/HEAD/tree.

Unlike Executor and Executor5, this repository includes everything from SourceForge: trunk, branches, releases, docs, tests, incubator, and sandboxes.

Documentation:

• Diary
• Unicode support
• Instructions to build Executor5-bulk
• Instructions to build ICU4ooRexx (optional)