*: new tls configuration for operator

[xhebox]

Signed-off-by: xhe xw897002528@gmail.com

What problem does this PR solve?

Issue Number: ref #69, ref #64

Problem Summary: TLS refine

What is changed and how it works:

1. use cluster-tls for cluster client secret
2. use server-tls for sql port, HTTP port
3. use sql-tls to connect TiDB sql port
4. use peer-tls for peer communication
5. add skip-ca, auto-certs
6. also apply these TLS config really, e.g. etcd will listen https if set server-tls, will check TiDB health by https if cluster-tls set
7. modify config manager to used etcd server instead of etcd client. Because if user pass a CA to server-tls, connect to 2379 may fail
8. use InsecureSkipVerify for CreateTLSConfigForTest, use DNS serverAddr instead of backendIO.RemoteAddr().String() if possible
9. fix a bug in newtidb logger that additional fields are not appended correct:

[xxxx] // before
[xxxx] [x1=] [x2=] // fixed

The tidb encoder will append like so:

[xxxxx] additional fields

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

Tested in k8s

• No code

Notable changes

• Has configuration change
• Has HTTP API interfaces change (Don't forget to add the declarative for API)
• Has weirctl change
• Other user behavior changes

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[djshow832]

What does this mean?
If you get the prefix of a string, why not just use string functions?

[xhebox]

Copy from etcd server source, in short the next nextLargestKey. It is not related to string or whatever.