delete log dir in clean task
Merge branch 'dev' into feature/autodetect_configuration

Conflicts:
	src/main/groovy/com/apphance/ameba/configuration/android/AndroidConfiguration.groovy
	src/main/groovy/com/apphance/ameba/configuration/ios/IOSConfiguration.groovy
	src/main/groovy/com/apphance/ameba/plugins/AmebaPlugin.groovy
	src/test/groovy/functional/com/apphance/ameba/android/ExecuteAndroidBuildsTest.groovy
	src/test/groovy/integration/com/apphance/ameba/plugins/android/buildplugin/tasks/CopySourcesTaskSpec.groovy
	src/test/groovy/integration/com/apphance/ameba/plugins/release/tasks/CleanReleaseTaskSpec.groovy
	src/test/groovy/integration/com/apphance/ameba/plugins/release/tasks/ImageMontageTaskSpec.groovy
additional log, tmp string replace. unit test fix
android single variant apk builder spec - warning, test works on an updated project only
plist parser, placeholder evaluator