bump versions for next release (#22)

Author: jwoertink

shard.yml

@@ -1,5 +1,5 @@
 name: carbon_sendgrid_adapter
-version: 0.5.0
+version: 0.5.1
 
 authors:
   - Matthew McGarvey <matthewmcgarvey14@gmail.com>

src/carbon_sendgrid_adapter.cr

@@ -6,7 +6,7 @@ require "./errors"
 require "./carbon_sendgrid_extensions"
 
 class Carbon::SendGridAdapter < Carbon::Adapter
-  VERSION = "0.5.0"
+  VERSION = "0.5.1"
   private getter api_key : String
   private getter? sandbox : Bool