MimeType category/signature implementation

[pjrinaldi]

need to address the mimetype issue with using extension, need to switch back to other mimetype and go from there or i need to use libmagic and do it all over again...

[pjrinaldi]

Go back to qtmime with just content and then implement my own extension code.

also move my custom type identification to the function so I only write it once and modify what I return.

[pjrinaldi]

working on integrating my customizations to the GenerateCategorySignature function to avoid redundancy and then remove the filename mimesignature.

just need to test and account for other datat types that aren't handled properly on my own... but this will come through testing different images with files.

[pjrinaldi]

working. still need to add other types as i come across them, but it is working as is, just needs more refinement