Fixed transpilation for classes with semicolons after class members.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72178648
Rework ES6 module support. Decouple from CommonJS pass.

Emit goog.provide / require calls for exported / imported modules.
Inject a module object for each exported module.
Change references of imported symbols to property accesses on the module objects.
Update JSdoc for imported types.

Currently, modules are named using toModuleName(filename), which prepends a "module$" prefix, removes leading ./, replaces / with $, removes trailing .js and replaces - with _.

TODO(moz): Support importing by both ES6 and ES3 modules via the @namespace JSDoc.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72185953