Implement RunPurger

[githubzilla]

Overall design

[githubzilla]

• The purger accept an URL as input parameter, e.g. "s3://eloqkv-bucket/db-cluster-name" or "http://172.168.20.27:9900/eloqkv-bucket/db-cluster-name"
• The purger will remove all unreferenced SST files under the given URL
• In the CP environment, the single object path purger must be disabled, otherwise several purgers can conflict with each other
• The purger must run in high frequency, e.g. once every hour, otherwise those unnecessary SST files after compaction will pile up

[githubzilla]

In coding, and we need to find a solution to address the bug of mistakenly removed SST file.

[githubzilla]

This work is connect with the Bug.
Its design is depends on how does the bug can be resolved.

[githubzilla]

Starting test

[holiday-404]

Change the end date from 9/11 to 9/19

[githubzilla]

rocksdb-cloud pr
store_handler pr

[githubzilla]

Trying to build improved_purger.cc as standalone application.

[githubzilla]

Code for remove manifest files