add an index position to block contexts
Merge branch 'master' into debugger
new browser icon
new interpreter based on a stack
adds Array >> #addFirst:
adds a test for Array >> #addFirst:
new interpreter passes the tests
- renamed Array 'adding' protocol to 'adding/removing'
- fixed Array >> #removeLast:
first (work in progress) stepping debugger
fix the interpreter to correctly interpret JS globals
more debugger and context improvements
Merge branch 'master' into debugger

Conflicts:
	js/boot.js
keep track of block position in the source code
better indentation for BlockClosure >> newValue* methods
- new interpreter
- helios debugger improvements
- recompiles all js files
some boot.js cleanup
Merge branch 'master' into debugger
Merge branch 'master' into debugger
Enhanced Amber REPL.
save previous results; Ctrl+L to clear screen