Bump tokio-imap version to 0.5.0-alpha.1

Author: djc

tokio-imap/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tokio-imap"
-version = "0.4.0"
+version = "0.5.0-alpha.1"
 authors = ["Dirkjan Ochtman <[email protected]>"]
 description = "Tokio-based IMAP protocol (client, for now) implementation"
 documentation = "https://docs.rs/tokio-imap"