Spelling fixes

* appropriate
* assumption
* attach
* because
* building
* customized
* mapping
* propagated

Signed-off-by: Josh Soref <jsoref@gmail.com>

cli/command/container/hijack.go

@@ -163,7 +163,7 @@ func (h *hijackedIOStreamer) beginInputStream(restoreInput func()) (doneC <-chan
 			if err != nil {
 				// This error will also occur on the receive
 				// side (from stdout) where it will be
-				// propogated back to the caller.
+				// propagated back to the caller.
 				logrus.Debugf("Error sendStdin: %s", err)
 			}
 		}

cli/command/container/start.go

@@ -146,12 +146,12 @@ func runStart(dockerCli *command.DockerCli, opts *startOptions) error {
 				fmt.Fprintln(dockerCli.Err(), "Error monitoring TTY size:", err)
 			}
 		}
-		if attchErr := <-cErr; attchErr != nil {
+		if attachErr := <-cErr; attachErr != nil {
 			if _, ok := err.(term.EscapeError); ok {
 				// The user entered the detach escape sequence.
 				return nil
 			}
-			return attchErr
+			return attachErr
 		}
 
 		if status := <-statusChan; status != 0 {