scripts: Renamed -w/--wait -> -t/--wait

I'm trying to avoid the inevitable conflict with -w/--word, which will
probably become important when exploring non-32-bit filesystem
configurations.

Renaming this to -t/--wait still conflicts with -t/--tree and -t/--tiny,
but as a debug-only flag, I think these are less important.

Oh, and -t/--trace, but test.py/bench.py are already quite different in
their flag naming  (see -d/--disk vs -d/--diff).

---

Renamed a few other flags while tweaking things:

- -t/--tiny -> --tiny (dropped shortform)
- -w/--word-bits -> -w/--word/--word-bits
- -t/--tree -> -R/--tree/--rbyd/--tree-rbyd
- -R/--tree-rbyd -> -Y/--rbyd-all/--tree-rbyd-all
- -B/--tree-btree -> -B/--btree/--tree-btree

After tinkering with it a bit, I think the -R/-Y/-B set of flags are a
decent way to organize the tree renderers. At least --tree-rbyd-all does
a better job of describing the difference between --tree-rbyd and
--tree-rbyd-all.

scripts/dbgleb128.py

@@ -111,7 +111,8 @@ if __name__ == "__main__":
             '-i', '--input',
             help="Read leb128s from this file. Can use - for stdin.")
     parser.add_argument(
-            '-w', '--word-bits',
+            '-w', '--word', '--word-bits',
+            dest='word_bits',
             nargs='?',
             type=lambda x: int(x, 0),
             const=0,