feat: refine mlog_dump output

[neverchanje]

What problem does this PR solve?

mlog_dump used to print two lines for a mutation, one line for mutation header, and the other for mutation content. Two lines make it inconvenient for data searching (grep/awk). So we combined the two into one line in this PR.

For most of our use cases of mlog_dump, it's used to search data in the specified time range, in order to find hotkeys, or find business-related information. However, the mutation timestamp is printed as long int like "timestamp=1582715060503806", not suitable for time search. So we format the timestamp into "YYYY-mm-dd hh:mm:ss.SSS". For example: "timestamp=2020-02-26 19:04:20.453".

Result:

mutation [22.29.210.2138042763]: gpid=22.29, ballot=210, decree=2138042763, timestamp=2020-02-26 19:04:20.453, last_committed_decree=2138042762, log_offset=407050443493, log_length=204, update_count=1 [CHECK_AND_SET] "796a743221c0985c469c0dab0e093688" : IF SORT_KEY(first-start:) CT_VALUE_NOT_EXIST THEN SET SORT_KEY(first-start:) => VALUE(1582715060453) [expire=0]

[acelyc111]

mutation [22.29.210.2138042763]: gpid=22.29, ballot=210, decree=2138042763, timestamp=2020-02-26 19:04:20.453, last_committed_decree=2138042762, log_offset=407050443493, log_length=204, update_count=1 [CHECK_AND_SET] "796a743221c0985c469c0dab0e093688" : IF SORT_KEY(first-start:) CT_VALUE_NOT_EXIST THEN SET SORT_KEY(first-start:) => VALUE(1582715060453) [expire=0]

Now that gpid, ballot and decree have been printed in [22.29.210.2138042763], how about remove the following gpid=22.29, ballot=210, decree=2138042763,

[levy5307]

这个不需要32位这么长吧？

[neverchanje]

22 bytes actually. 32 is for memory alignment.