This PR adds a fake controller client for local CLI operations like
offline spec generation or for unit test purposes. The fake client
now only implements the "Version()" function and more functions
will be implemented once we figure out how to achieve the goals
mentioned above.
To keep archive creation implementation simple and prevent any
confusion, we decided to remove `--keepurl` flag and embed URL
directly without downloading the file from it . In this way, we can
ensure consistent behavior in either package creation or spec file
creation. Also, it increases the portability of spec file.
1. The records are stored in redis which is not migratable to another cluster for the testing purposes.
2. Some of the requests fields are not recorded.
3. People should consider using https://github.com/buger/goreplay which is an existing mature and well-tested solution for testing purposes.