Prepare for a special release

Some vocal user asked for this. Do not use it, it uses a version of
cbindgen with a known bug that leads the creation to a faulty C-API that
would crash horribly when used.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cargo-c"
-version = "0.6.10"
+version = "0.6.11-cbindgen-0.14.3"
 authors = ["Luca Barbato <lu_zero@gentoo.org>"]
 description = "Helper program to build and install c-like libraries"
 license = "MIT"
@@ -28,7 +28,7 @@ semver = "0.9"
 log = "0.4"
 structopt = "0.3"
 regex = "1"
-cbindgen = "0.14.2"
+cbindgen = "=0.14.3"
 toml = "0.5"
 serde = "1.0"
 serde_derive = "1.0"