BamRead.toMsgpack

Packs message in the following format:
MsgPack array with elements

1. name - string
2. flag - ushort
3. reference sequence id - int
4. leftmost mapping position (1-based) - int
5. mapping quality - ubyte
6. array of CIGAR operation lengths - int[]
7. array of CIGAR operation types - ubyte[]
8. mate reference sequence id - int
9. mate position (1-based) - int
10. template length - int
11. segment sequence - string
12. phred-base quality - ubyte[]
13. tags - map: string -> value