Update license in S3M, FLT and MDL loaders

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Minor refactoring and reindent of FLT loader

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Update changelog

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>