Signal an error if nREPL is disconnected

This replaces the error "Wrong type argument: stringp, nil"
with something a little more clear.
Merge pull request #406 from dgtized/signal-error-if-not-connected

Signal an error if nREPL is disconnected
[Fix #407] Handle the case when CIDER is not installed via package.el

We cannot obtain a package version when there is no package to obtain it from.
Autoload cider-selector
Extract cider-selector tests into a separate file
Extract bencode tests
Rename nrepl-tests.el to cider-tests.el
Minor comment fix
Extract error parsing tests
Apply ANSI color to all output
Add pkg file
Add package building task
Release 0.3.0
Fix package generation task
Ignore the packages dir
Fix library version discovery bug
Fix function name
[Fix #408] Bump version to 0.3.1
Refactor package generation code

cider-pkg.el is now auto-generated by cask.

Special thanks to @lunaryorn for suggesting this.
Start work on the 0.4.x series