Fixes Regression in 2.2 - menu.xml config ignored

[fooman]

Description

Fixes regression introduced with commit fooman@24b608a
dependsOnModule, dependsOnConfig, toolTip should match casing mandated by menu.xsd
please also note which already has the correct values.

Manual testing scenarios

1. setup a module with

    <!--menu.xml-->
    <?xml version="1.0"?>
    <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Backend:etc/menu.xsd">
        <menu>
            <add id="Fooman_Example::test"
                 parent="Magento_Sales::sales"
                 resource="Fooman_Example::test"
                 module="Fooman_Example"
                 title="Fooman Example"
                 sortOrder="20"
                 action="foomanexample/test"
                 dependsOnConfig="foomanexample/menu/display_test"/>
        </menu>
    </config>

2. Make sure foomanexample/menu/display_test is a false value
3. Observe that the menu item is not visible

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)