gen C++ encoder should be more consistent in spacing

[jbsolomon]

0x00,0x00,0x00,0xfd,0x00,0x01,0x00,0x38,0x00,0x01,0x00, // |...ý...8...|
0x00,0x00,0x00,0x00, // |....|
// ISSUE: ^^^ This line should be longer instead of split into two, and comments right-justified.
0x53,0x71,0x3b,0x4d, // |Sq;M|