Bugfix/nicolas more fixes (#36)

* FIX: Remove the serde_json depndendency

* UPDATE: Use binary representation also for languages and locales

Cargo.lock

@@ -370,7 +370,6 @@ dependencies = [
  "ryu",
  "serde",
  "serde_json",
- "serde_repr",
 ]
 
 [[package]]
@@ -679,17 +678,6 @@ dependencies = [
  "serde",
 ]
 
-[[package]]
-name = "serde_repr"
-version = "0.1.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b2e6b945e9d3df726b65d6ee24060aff8e3533d431f677a9695db04eff9dfdb"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
 [[package]]
 name = "sha1"
 version = "0.10.6"