Audio Themes 5.1-beta

Changes from 5.0-beta:

• Major security and performance enhancements
• Added support for ogg audio format.
• The add-on is now aware of if NVDA is running in a secure mode and changes its options accordingly.
• All the dialogs are now correctly centred in the screen.
• The themes options (such as: Play in 3D mode and use synth volume) will no longer be enabled if the Disable audio themes option is activated.
• The add-on uses config.conf as its configuration facility
• The add-on was updated to the upstream add-on template
• In the audio themes manager, themes now show whether they are active or not
• Minor bug fixes.