Reduce MP3 False-Positives

[Kevin-McGonigle]

Currently, the MP3Parser is very lenient with what it attempts to parse, leading to it attempting to parse a number of file formats that it shouldn't. This has necessitated a number of edge case checks being added to skip formats that are known to be affected. It's likely that there are numerous unknown edge cases, though, and the parser itself should be made more robust so that it only attempts to parse MP3 files.