Fix a typo and a "tag value" that has been overlooked.

src/reader.rs

@@ -75,7 +75,7 @@ impl Reader {
         }
 
         // Cheat on the type system and erase the lifetime by transmute().
-        // The scope releases the innter `v` to unborrow `buf`.
+        // The scope releases the inner `v` to unborrow `buf`.
         let (v, le) = {
             let (v, le) = try!(tiff::parse_exif(&buf));
             (unsafe { mem::transmute(v) }, le) };

src/tag.rs

@@ -93,7 +93,7 @@ impl fmt::Display for Tag {
     }
 }
 
-/// An enum that indicates how a tag value is interpreted.
+/// An enum that indicates how a tag number is interpreted.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 pub enum Context {
     /// TIFF attributes defined in the TIFF Rev. 6.0 specification.