Changelog
csvtk: supporting multi-line fields by replacing multicorecsv with standard library encoding/csv,
while losing support for metaline which was supported since v0.7.0. It also gain a little speedup.csvtk sample: add flag-n/--line-numberto print line number as the first column ("n")csvtk filter2: fix bug when column names start with digits, e.g.,1000g2015aug(#44)csvtk rename2: add support for similar repalecement symbols{kv} and {nr}incsvtk replace