Update license in core player files

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Update core player macro name

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

Conflicts:
	src/format.c
Address unused variable compiler warning

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