* MM-14446: consider subpath when evaluating if url is internal
When clicking on an URL with `target=_blank`, the webview decides if it should launch an external browser or a new window within the Electron application. Update this logic to consider the application's configured subpath so as to treat links outside the subpath but on the same domain as external.
* fix licensing on new file
* fix .eslintrc.json indentation
* tweak header eslint rules for specific files
Multiple async tasks were not performed completely when running uninstaller.
So rearranged tasks with sequential order.
i.e. take care startup registry, finally call electron-squirrel-startup.
