Assert needed for missing file path (art/sound problems)

[raxo2222]

Units, buildings, and other stuff have various ART and sound defines.

They lead to art/sound define files, which then reference file path.

When file actually doesn't exist, game should throw asserts.

Example:
ART_DEF_UNIT_TRIBAL_GUARDIAN in units infos
UNIT_TRIBAL_GUARDIAN in unit art style defines
ART_DEF_UNIT_TRIBAL_GUARDIAN in unit art defines
Art/Units/Spikedclub/warrior_fx.nif this file is not found.

Sound:
AS2D_UNIT_BUILD_UNIT in unit art defines
SND_BUILD_UNIT in audio2dscripts
Sounds/Units/BuildUnit this file is not found.

If this chain doesn't end up on file path, then assert would show up earlier, and say: "Malformed art/sound define"

It also can be done for text:
If things referencing TEXT have missing texts, then it also could assert.
Or simply create log file with all art/sound/text reference chains, so we can see in logs what exactly is missing file or text entry in TEXT file.

[raxo2222]

This is very important so we can verify, that we won't get sound errors or pink units (multiple textures for multiple unit artstyles - we have 30 or so unit artstyles).

On other hand unused art/sound assets needlessly take memory - those should also be cleared up.

[raxo2222]

#418
Seems like I forgot about it and made new issue.

Currently Text validator is under development.