Before this change Fields() method on a metric parsed from a line with
unescaped quotes could panic. This change makes such line unparseable.
Fixes#3326
main reasons behind this:
- make adding/removing tags cheap
- make adding/removing fields cheap
- make parsing cheaper
- make parse -> decorate -> write out bytes metric flow much faster
Refactor serializer to use byte buffer
This constitutes a large change in how we will parse different data
formats going forward (for the plugins that support it)
This is working off @henrypfhu's changes.
Daniel Nelson
faye-sama
Cameron Sparr