Rotate and display nrepl connection
Merge pull request #359 from jonpither/rotate-and-display

Rotate and display nrepl connection
Kill some tabs
More robust version reporting

The version reporting is now based on the pkg-info package. Clojure
version reporting was moved to the connection info, since it's
connection specific information.
[Fix #362] Update version logic in the welcome banner
Add missing require for pkg-info

Caused the following byte-compilation warning:


nrepl.el:3387:1:Warning: the function `pkg-info-format-version' is not known to be defined.
Fix `nrepl-switch-to-repl-buffer' to work with all connections

Commit 12558e8 breaks `nrepl-switch-to-repl-buffer' functionality by
assuming that all nrepl connections will be made using
`nrepl-jack-in'.

Using `nrepl-jack-in' sets the variable `nrepl-project-dir' to the
correct value, but this information cannot be retrieved when we
connect to an existing nRepl server using `nrepl-connect'. Since
`nrepl-project-dir' is unbound, the function `file-truename' throws a
null value exception.

This commit checks if `nrepl-project-dir' is set before calling
`file-truename'. Further, the message "nREPL connection not found"
does not make sense and thus should not be displayed.
Revert to old nrepl-switch-to-repl-buffer.

Add the new functionality defined in 12558e8 as a separate
`nrepl-switch-to-relevant-buffer` function.
Add documentation and key-bindings for `nrepl-switch-to-relevant-buffer'
Add tests for `nrepl-switch-to-relevant-buffer'