Minor wording tweaks.
Add a props file for 3rd party libraries.

This way, we'll be able to use separate settings more easily.
Project files: remove unneeded properties.
Update unrar to v5.2.1.
Initializer list order fixes.

Found with cppcheck (inconclusive enabled).
Remove empty CString variables initialization.
Fix rebase issue after 2a0054b97cfa1e434e83016b6c1d5a2fb555956f.
Fix some possible loss of data warnings on x64.
PlayerNavigationDialog: Remove unreachable code.
PlayerNavigationDialog: Initialize m_bChannelInfoAvailable.
Don't force any background color for the Shockwave graph.

This commit fixes #1747.
WebUI: Inform the web interface that no audio stream is available.