Merge pull request #1 from daitangio/master

readme: using python to serve http pages.
fix primitiveNewMethod
add example for external modules
demo: include SimplePlugin.js in offline cache
SimplePlugin: fix stack
GC: mark objects only once
Add continuation support to main loop
Use IndexedDB for local file storage
Keyboard works much better if implemented as queue, not stack

Duh!
Implement real imageName primitive
Don't pass around compactClasses, mark classes instead
Use actual oops instead of ids
Use words in size calculation
GC: do not trace context slots above stack pointer
Include one header word in body size
Implement image saving
Get rid of nextTempOop, use newSpaceCount instead
Fail fileGet() if file not found
Move MiscPrimitivePlugin in file
Provide static Squeak.totalSeconds()