GPII-153: Implement the Speak Text adjuster group

You can see the different views and spaces of the Speak Text adjuster group here: http://wiki.fluidproject.org/display/fluid/%28C4A%29+Preference+Editor+adjuster+mockups+for+iteration+2 (right column).

You can see the demo of Speak Text by running the file demos / speakTextAdjusterGroup / index.html in node-webkit.

The whole code directly related to the adjuster group is in the src / shared / adjusters directory.
The Fluid UI Options Preference Framework is used for creating and linking the separate adjusters into one group. The primary schema is defined in the schemas.js file, animation and text fields are defined declaratively in speakText.js. Each of the adjusters' panels is defined in the speakTextPanels.js file and they are combined together into a collective panel by grade merging. The collective panel is situated in the speakTextCollectivePanel.js file.