Added test case
Added 'strict'-boolean on JavaScript asset to keep track of global strict mode expressions
Detect global 'use strict' directives
transforms/bundleRelations: When adding a script to a bundle that has a global 'use strict'-directive, emit a warning that this might have side effects
Merge pull request #163 from One-com/globalstrict

Warn when concatenating scripts that might leak strict mode to the global scope