The ARA SDK's debug functionality is included in the audio_processors
module, hence the configuration had to be moved there from
juce_plugin_client.

This includes Carbon support

These were mistakenly removed in afe5199848

Previously, right-clicking on a slider could change its value, but the
parameter value would not be changed, leaving the slider in a different
state to the parameter.

This commit removes the various compiler-specific JUCE_DEPRECATED macros and replaces them with C++14's deprecated attribute. It also removes the JUCE_CATCH_DEPRECATED_CODE_MISUSE flag as we can rely on the override specifier catching usage of these old virtual methods, and tidies up the DOXYGEN preprocessor checks as they were inconsistent across the codebase.