Changed default GSB endpoint to UNIX socket

[Wiezzel]

Testing instructions:

1. Run yagna and look for message about GSB listening on UNIX socket.

$ cargo run service run
[2021-02-09T16:08:51Z INFO  yagna] Starting yagna service! Version: 0.6.0-rc6 (4e6629dc 2021-02-08).
Log is written to /home/adam/yagna/test/yagna_rCURRENT.log
[2021-02-09T16:08:51Z INFO  yagna] Data directory: /home/adam/yagna/test
[2021-02-09T16:08:51Z INFO  ya_sb_router] Router listening on: "/tmp/yagna.sock"

2. Check file permissions (should be 700 – only owner allowed to connect).

$ stat /tmp/yagna.sock
  File: yagna.sock
  Size: 0               Blocks: 0          IO Block: 4096   socket
Device: 804h/2052d      Inode: 4332642     Links: 1
Access: (0700/srwx------)  Uid: ( 1001/    adam)   Gid: ( 1001/    adam)
Access: 2021-02-09 17:58:24.924073454 +0100
Modify: 2021-02-09 17:58:24.556082429 +0100
Change: 2021-02-09 17:58:24.556082429 +0100
 Birth: -

3. Run some CLI commands and check if they work.

[pnowosie]

Nice work!

[Wiezzel]

@maaktweluit Bump

[maaktweluit]

Whoops! my review from Thursday was still pending..

Please update the commit to ya-service-bus after the other PR got merged

besides that:
LGTM!

[maaktweluit]

LGTM!