Change default rollover conditions to 2 days

[pavolloffay]

Change default rollover conditions from 7 days to 2 days.

Given that by default Jaeger uses daily indices and some organizations do not keep data longer than 7 days the default of 7 days seems unreasonable - it might result in a too big index and running curator would immediatelly remove the old index.

We should be more careful and change the default to 2 days - double the default daily indices. Is anybody from @jaegertracing/elasticsearch running rollover? Can anybody share the experience with this?

[codecov]

Codecov Report

Merging #1963 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1963   +/-   ##
=======================================
  Coverage   96.99%   96.99%           
=======================================
  Files         203      203           
  Lines       10061    10061           
=======================================
  Hits         9759     9759           
+ Misses        264      263    -1     
- Partials       38       39    +1

Impacted Files	Coverage Δ
cmd/collector/app/http_handler.go	100% <0%> (ø)	⬆️
plugin/storage/badger/spanstore/reader.go	96.79% <0%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 730170d...b799d3e. Read the comment docs.

[yurishkuro]

before merging please add a note to CHANGELOG

[pavolloffay]

Changelog added. I have reformatted changelog for 1.16 to match older version style.

[yurishkuro]

I intentionally modified the formatting for 1.16 to make it easier to read, as well as to fix the incorrect L+1 header levels. I think using the new format is better going forward, and there's no particular reason why it has to match exactly previous versions.

[pavolloffay]

I have changed back the heading sizes to bigger ones as you proposed.

[yurishkuro]

why not leave it as is? Each breaking change has its own section with a proper header, makes it easier to read than a long bullet list. Bullet lists are used for short collection of items, not for page+ long descriptions with examples.

[pavolloffay]

Each breaking change has its own section with a proper header, makes it easier to read than a long bullet list.

I think it looks worse and also it mixes styles - some sections are using a list and other header. However headers allow us to reference specific sections which is useful for breaking changes.

I have changed breaking changes to headers - however keep the same header structure as for list and include it under backed changes.