Update charlock_holmes to 0.7.3

Version 0.6.9.4 fails to install on Gentoo Linux.

Update charlock_holmes to 0.7.3
c217860a · Jakub Jirutka · d785b20c · c217860a
Commit c217860a authored 10 years ago by Jakub Jirutka
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -74,7 +74,7 @@ GEM
      json (>= 1.7)
    celluloid (0.16.0)
      timers (~> 4.0.0)
-    charlock_holmes (0.6.9.4)
+    charlock_holmes (0.7.3)
    cliver (0.3.2)
    coderay (1.1.0)
    coercible (1.0.0)