Update libmongoc to 1.6.3

Cargo.toml

@@ -19,7 +19,7 @@ bson = "> 0.1.0"
 
 [dependencies.mongoc-sys]
 path    = "mongoc-sys"
-version = "1.5.3"
+version = "1.6.3"
 
 [dev-dependencies]
 chrono = "> 0.2.0"

mongoc-sys/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name        = "mongoc-sys"
-version     = "1.5.3"
+version     = "1.6.3"
 description = "Sys package with installer and bindings for mongoc"
 authors     = ["Thijs Cadier <thijs@appsignal.com>"]
 build       = "build.rs"

mongoc-sys/build.rs

@@ -2,7 +2,7 @@ use std::env;
 use std::path::Path;
 use std::process::Command;
 
-static VERSION: &'static str = "1.5.3"; // Should be the same major version as in the manifest
+static VERSION: &'static str = "1.6.3"; // Should be the same major version as in the manifest
 
 fn main() {
     let out_dir_var = env::var("OUT_DIR").unwrap();