Add version command line argument

* -V and --version now print the program version and exit
* Use the `exitcode` crate
* Rename `options` variable to `accepted_args`, which seems clearer
  given its usage.

1 files changed, 1 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 368b968..58bf90f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,4 +4,5 @@ version = "0.5.0"
 
 [dependencies]
 clipboard = "0.1.2"
+exitcode = "1.1.2"
 rustty = "0.1"