libstd: set baseline stability levels.

Earlier commits have established a baseline of `experimental` stability
for all crates under the facade (so their contents are considered
experimental within libstd). Since `experimental` is `allow` by
default, we should use the same baseline stability for libstd itself.

This commit adds `experimental` tags to all of the modules defined in
`std`, and `unstable` to `std` itself.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/libstd/from_str.rs b/src/libstd/from_str.rs
index 642bec48b83..1ca72bca20b 100644
--- a/src/libstd/from_str.rs
+++ b/src/libstd/from_str.rs
@@ -10,6 +10,8 @@
 
 //! The `FromStr` trait for types that can be created from strings
 
+#![experimental]
+
 use option::{Option, Some, None};
 use string::String;
 use str::StrAllocating;