Update browser recommendations
Merge pull request #6 from timfel/patch-1

Update browser recommendations
Fake indexedDB by storing files in memory (not persistent)
gc: deal with nil stack pointer in Context object
demo: extend harness
vm: remove livelyism
demo: comment harness
GC: remove unneeded relink step
GC: unmark first object (for aesthetic reasons)
Clean context garbage during GC, not only when snapshotting
benchmark image