Added a build script.

The build script was added to obtain the correct values of the
errno C preprocessor definitions. This way no matter what the platform
has defined them as, they will be correct in the libraries code.

Cargo.toml

@@ -7,18 +7,26 @@ license = ""
 repository = "https://gitlab.com/CyberMages/pact.git"
 documentation = ""
 keywords = ["c", "libc", "binding", "ffi", "pact", "nostd"]
+build = "build.rs"
 
 
 [features]
 default = []
-use_std = ["scribe/use_std", "binding/use_std"]
+use_std = ["scribe/use_std", "binding/use_std", "weave/use_std"]
 rust_lib = []
 no_mem_manip = []
 weak = []
 
 
+[build-dependencies.scribe]
+git = "https://gitlab.com/CyberMages/scribe.git"
+
+
 [dependencies.scribe]
 git = "https://gitlab.com/CyberMages/scribe.git"
 
 [dependencies.binding]
 git = "https://gitlab.com/CyberMages/binding.git"
+
+[dependencies.weave]
+git = "https://gitlab.com/CyberMages/weave.git"