This header contains a (possibly empty) list of predefined palettes that may be referred to by data packets. This header is mandatory, even if no palettes are predefined.
As with all headers, the first 8 bytes are composed of the header type (0x86) and the 7 byte kate signature ("kate\0\0\0").
Next, we find a variable length integer, holding the number of predefined palettes this header contains. A negative value is an error.
Next, we find a list of palette definitions, as many as defined int the previously read number.
Next, we find a warp.
Next, the data ends.