updated CHANGELOG and gradle build file for 2.0.1 release

updated version infos

Merge branch 'v2.0'

updated binary for v1.8

updated version property in gradle build file

updated starling binary for v1.6

updated maven pom.xml for v1.5.1

updated swc file for 1.5 release

updated binary for version 1.4.1

new compilation for v1.4, including last AssetManager change