bump version to 1.0.0-pre4

bump versions to pre3 and remove versions.json file

bump version to 1.0.0-pre1

bump meteor version 0.9.1-rc2

update versions file

Merge branch 'devel'

add blaze-layout to smart.json even though we don't use it

so that in package.js we can create a weak reference to it.

support passing {flush: true|false} to endRendering

add smart.json and history file prepare for atmosphere release