Feature/TTS SSML Tagging

[ryrutherford]

• Redesign the TTSaaS page to give users the ability to easily add SSML tags to their text
  • The supported tag and attribute combinations are:
    • prosody (with the timbre, pitch, and rate attributes)
    • break (with the strength and time attributes)
    • style (with the name attribute)
    • voice (with the name attribute)
  • Users can select text and then choose the tag and attribute/value combination they want to apply to the selected text
  • As soon as an SSML tag is added to the text, the SSML option is enabled so that any synthesized text will use SSML
  • If the chosen tag/value combination requires more input (e.g. they chose the prosody tag with a relative percentage pitch) then the cursor will move to the location where more input is needed
• Fixed an issue where no error was being displayed and the synthesize button became disabled when the user enters valid SSML but the request times out (this would occur occasionally when using the voice tag)