Different name from the main view tab bar.

This setting applies to My View's tab bar.
[JENKINS-13035] Changed the field name.

Now it gets the right property. The dropdown shows the values
for MyViewsTabBar extension
and there is help icon and text.
[JENKINS-13035] Only show this option when more than 1
MyViewTabBar available.
[FIXED JENKINS-13035] Merge pull request #1141
Merge branch 'master' of github.com:jenkinsci/jenkins