version to 1.0.0.rc1

* quiet mode - added a `--quiet` flag to the init command (#32)
* `exec` command - execute a command using a specific ruby version (#31)
* change auto handling to use the `PROMPT_COMMAND` env var (#30)
* set RUBY_ROOT env var (#29)
* resolve ruby versions symlinks when applying to the env (#28)
* more succinct help msg (#27)