Issue #48 & Issue #67: debugger, process browser, `ps` command enhancements

- Object keyboard shortcuts for debugger
- bring up process printString when process selected in process browser
- add `portable` menu item for process browser (convert to portable from native)
- `ps portable` command implement in TDProcessTool to make it possible to
  set breakpoints in same process instance where you want them active
When selecting class in hierarchy pane, update all 3 (or 4) client elements at once
Issue #67: continue switch over from TDDebugTool-based to TDDebugger-based debugging, knitting together more of the debugger functionality.

- tweak TDProcessTool ...
- TDTopezServer>>clientElementFor:using: needs to add clientElement to elementCache
handle debugger conditions in return value boy