Add the missing _

The error messages use the _() gettext function, which wasn't imported.

Change-Id: If515e405dcc895073643681a5e822f12ba9b9ef7
RST typo for tutorial documentation

Change-Id: Iefde2978d37363993fa1e10001510aca1a73e9c1
Signed-off-by: Paul Belanger <paul.belanger@polybeacon.com>
Merge "Add the missing _"
Merge "RST typo for tutorial documentation"