Cleanup typos and newlines

src/comp/middle/trans.rs

@@ -5388,7 +5388,7 @@ fn trans_block(@block_ctxt cx, &ast.block b) -> result {
 
                 if (ty.type_is_boxed(r_ty)) {
                     // The value resulting from the block gets copied into an
-                    // alloca created in an outer scope and it's refcount
+                    // alloca created in an outer scope and its refcount
                     // bumped so that it can escape this block. This means
                     // that it will definitely live until the end of the
                     // enclosing scope, even if nobody uses it, which may be

src/test/run-pass/expr-alt.rs

@@ -28,4 +28,4 @@ fn test() {
 
 fn main() {
   test();
-}
+}

src/test/run-pass/expr-block-box.rs

@@ -7,4 +7,4 @@ fn main() {
   };
 
   check (*x == 100);
-}
+}