Changed NonCamelCaseTypes lint to warn by default

Added allow(non_camel_case_types) to librustc where necesary

Tried to fix problems with non_camel_case_types outside rustc

fixed failing tests

Docs updated

Moved #[allow(non_camel_case_types)] a level higher.

markdown.rs reverted

Fixed timer that was failing tests

Fixed another timer

src/test/compile-fail/lint-dead-code-1.rs

@@ -10,6 +10,7 @@
 
 #[no_std];
 #[allow(unused_variable)];
+#[allow(non_camel_case_types)];
 #[deny(dead_code)];
 
 #[crate_type="lib"];

src/test/compile-fail/lint-dead-code-3.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 #[allow(unused_variable)];
+#[allow(non_camel_case_types)];
 #[deny(dead_code)];
 
 #[crate_type="lib"];

src/test/compile-fail/lint-unused-import-tricky-names.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 #[deny(unused_imports)];
+#[allow(non_camel_case_types)];
 #[allow(dead_code)];
 
 // Regression test for issue #6633