helios changes:
- adds "Widget" to widget class names
- adds HLWidget >> openAsWidget
HLListWidget navigation: prevent scrolling of parent div
helios: flush any progress bar on error
Make ConsoleTranscript actually print

ConsoleTranscript used to try and print an undefined variable (string)
to the browser's console, instead of the object sent via the 'show:'
message.
Wrap Javascript objects before showing

Nicolas reminded me that JS objects can't respond to __asString(), and
so must be wrapped. This is done via _st(), which will wrap the object
in a JSObjectProxy. Initial tests seem to indicate that this is enough -
I was able to print the Window object and some other JS objects.
Updated server.bat to use the latest amber-cli
Merge pull request #488 from mumez/batchFix

Updated server.bat to use the latest amber-cli
helios: progress bar flush fix
Test printing a JS object that exists everywhere

I don't have access to the `window` object when running Amber on Node,
and probably in other places. The `console` object seems to be pretty
universal.
Merge pull request #487 from kpullen/fixing-up-transcript

Make ConsoleTranscript actually print
adds Error >> #resignal
helios: a bit more flat look
Add class comments for some Helios-Announcements
Add SystemAnnouncement class>>heliosClass
Add announcement image and class
Merge remote-tracking branch 'remotes/johnyt/announcements'
helios: some list css tweaks
Use Error >> #resignal in BlockClosure >> #on:do:
Add a semicolon to the end of class comment lines in exported JS
Recompile JS for commented classes