Only list extant explicit version
Including test for specific version listing

This fixes the issue of nvm ls v[:digit:].[:digit:].[:digit:] listing the version even if it isn't available
Merge pull request #432 from ajcrites/master

Only list extant explicit version
redirect errors to stderr
redirect stderr to stdout in test
Merge pull request #436 from koenpunt/stderr

redirect output of errors to stderr
Suppress output of `nvm use`

+redirect errors to stdout
Merge pull request #438 from koenpunt/patch-2

Suppress output of `nvm use`
v0.8.0
Returning exit code 3 when no version is found.
Consistently returning exit code 1 when version is not installed yet.
Return the exit code of `nvm use` when `nvm install`-ing.
Removing reference to NVM_PROFILE in README. Fixes #442
Silently support `nvm i x.x.x`. Fixes #443.
Making sure there's test coverage for `nvm i`
Separating variable declaration from first assignment, which should fix some ksh problems.
Use printf instead of `echo -e`

Fixes #446
v0.9.0
Make sure `nvm ls foo` returns a nonzero exit code when a version is not found.

Fixes #440.
Make sure these vars are local, where supported