Fix incorrect package version in Cargo.lock.

--- a/Cargo.lock
+++ b/Cargo.lock
@@ -57,7 +57,7 @@
 
 [[package]]
 name = "exa"
-version = "0.11.0-pre"
+version = "0.10.1"
 dependencies = [
  "ansi_term",
  "datetime",