Parse / Deserialize outdated names

[CryZe]

While the code values spec only allows very specific names, in practice (even the latest versions of) browsers still use values that predate the spec, such as:

Old Meta Values

• OSLeft for MetaLeft (Chrome <52, all Firefox versions, all Safari GTK and WPE versions)

• OSRight for MetaRight (Chrome <52, all Firefox versions, all Safari GTK and WPE versions)

  Firefox Tracking Issue

  Old Volume Values

• VolumeDown for AudioVolumeDown (Chrome <52, all Firefox versions)
• VolumeMute for AudioVolumeMute (Chrome <52, all Firefox versions)

• VolumeUp for AudioVolumeUp (Chrome <52, all Firefox versions)

  Firefox Tracking Issue

  Accidentally used key value for code (?)

• LaunchMediaPlayer for MediaSelect (all Safari GTK and WPE versions)