Remove unused files

The `doc`, `locale` and `test` directories only contain placeholder
files, this makes it harder for a new maintainer to understand the
structure of the project so I simply removed them. Removed the
`package.json.backup` as well, it's a git repository, no need to keep
`.backup` files.
Whitespace

Remove trailing whitespace
Replace all tabs with spaces for consistency
Remove execution permissions from files

Some files had the execution permissions flag set, some had not. This
commit removes that permission from all of them.