Added PEM and crx files
Chrome creates .crx and .pem files for a packaged extension outside of the directory which creates a signiture or key for the extension. This key must be used everytime the extension is repackage so that chrome doens't mistake it for a new package. In order to ensure that the extension will just be over written, I've refactored the repository to include the extension file (.crx) and it's key file (.pem). All source files are now located in the source folder.