fix build err(second build occurs)
clean static files and dynamic files after compile
Fixed #5354: Specify js version to ECMASCRIPT5 in build.xml for google closure
Merge pull request #118 from pandamicro/develop

Fixed #5354: Specify js version to ECMASCRIPT5 in build.xml for google c...
Add --host arg to project_run plugin
Merge pull request #119 from NekR/develop

Add --host arg to project_run plugin
remove static and dynamic files during precombile
Merge pull request #117 from bofeng-song/develop

clean static files and dynamic files after compile