Remove redundant imports in lib (rustc doesn't like 'std' as a synonym for...

Remove redundant imports in lib (rustc doesn't like 'std' as a synonym for root within std.rc anyway)

src/lib/_int.rs

-import std.sys;
 
 fn add(int x, int y) -> int { ret x + y; }
 fn sub(int x, int y) -> int { ret x - y; }

src/lib/_str.rs

 import rustrt.sbuf;
 
-import std._vec.rustrt.vbuf;
+import _vec.rustrt.vbuf;
 
 native "rust" mod rustrt {
     type sbuf;

src/lib/_uint.rs

-import std.sys;
 
 fn add(uint x, uint y) -> uint { ret x + y; }
 fn sub(uint x, uint y) -> uint { ret x - y; }

src/lib/_vec.rs

 import vbuf = rustrt.vbuf;
-import std.option;
 
 type operator2[T,U,V] = fn(&T, &U) -> V;
 

src/lib/bitv.rs

-import std._uint;
-import std._int;
-import std._vec;
-
 // FIXME: With recursive object types, we could implement binary methods like
 //        union, intersection, and difference. At that point, we could write
 //        an optimizing version of this module that produces a different obj

src/lib/dbg.rs

@@ -5,8 +5,6 @@
  * logging.
  */
 
-import std._vec;
-
 // FIXME: handle 64-bit case.
 const uint const_refcount = 0x7bad_face_u;
 

src/lib/deque.rs

@@ -2,10 +2,6 @@
  * A deque, for fun.  Untested as of yet.  Likely buggy.
  */
 
-import std.option;
-import std._vec;
-import std._int;
-
 type t[T] = obj {
             fn size() -> uint;
 

src/lib/io.rs

-import std.os.libc;
-import std._str;
-import std._vec;
-
+import os.libc;
 
 type stdio_reader = state obj {
                           fn getc() -> int;

src/lib/list.rs

-
-import std.option;
 import option.some;
 import option.none;
 

src/lib/map.rs

@@ -3,12 +3,6 @@
  * use, but useful as a stress test for rustboot.
  */
 
-import std._int;
-import std.sys;
-import std.option;
-import std._vec;
-
-
 type hashfn[K] = fn(&K) -> uint;
 type eqfn[K] = fn(&K, &K) -> bool;
 

src/lib/sha1.rs

@@ -4,9 +4,6 @@
  * point this will want to be rewritten.
  */
 
-import std._vec;
-import std._str;
-
 export sha1;
 export mk_sha1;