Switch from error-chain to thiserror (#33)

thiserror provides a simpler interface than error-chain, directly
generating an error enum similar to what could be written by hand. It
also reduces dependencies; error-chain pulls in backtrace which
currently pulls in gimli, which is fairly heavyweight.

This changes the error type's interface, so it'll require a bump to
0.7.0.

1 files changed, 0 insertions, 2 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 3dae164..7bf11ba 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -203,8 +203,6 @@
 )]
 
 #[macro_use]
-extern crate error_chain;
-#[macro_use]
 extern crate serde;
 
 #[cfg(feature = "actix")]