Added --set-time-path and --get-time-path for issue #10

Pretty simple really. Read the path from a config file, use the current working directory if there is no config. Checks for valid syntax of the flag and valid .json path.

```
--set-time-path                          will fail
--set-time-path=/test/dir/               will fail
--set-time-path=/test/dir/file.js        will fail
--set-time-path=/test/dir/file.json      will pass
```

Oh yeah, have to include a blank config file in the module because if we install globally we can't guarantee the access to create one.