Reduce how much projectile hits the server in TRAMP buffers by:
- Not looking for fd/fdfind (just use the VCS-specific commands
projectile provides and assume they're present on the remote).
- Not walking up the directory tree to display the project name in the
mode line.
- Reducing TRAMP file-cache misses.
- Reducing how chatty tramp is about its connections.
Fix#5360