Proto commits in ptt/pttbbs

These 5 commits are when the Protocol Buffers files have changed:

Commit:e637fdc
Author:Robert Wang
Committer:Robert Wang

boardd: Search API.

The documentation is generated from this commit.

Commit:2f35a7b
Author:Robert Wang

boardd: Should use uint32 for bid in BoardRef.

Commit:772fa2c
Author:Robert Wang
Committer:Robert Wang

boardd: implement Content method.

Commit:d44234f
Author:Robert Wang
Committer:Robert Wang

boardd: add grpc protocol.

Commit:6461cbb
Author:Robert Wang
Committer:Robert Wang

mand: A new daemon for man service.