data: Improve serialization of binary data.
data: Improve serialization of binary data.

Instead of calling strbuf_append() for each byte, precompute the string in a
simple for-loop and then append the result to the buffer. This basically
inlines a formatter specific to this use-case and, thus, should be must
faster.

tokkee/sysdb,tokkee/sysdb,sysdb/sysdb,sysdb/sysdb,tokkee/sysdb,sysdb/sysdb