Repository: nvm
Issue: nvm uninstall does not work
Labels: uninstalling,needs followup

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- Operating system and version:
MacOS High Sierra v10.13

- `nvm debug` output: 
<details>
<!-- do not delete the following blank line -->

```sh
nvm --version: v0.33.6
$TERM_PROGRAM: iTerm.app
$SHELL: /bin/zsh
$HOME: /Users/nibo
$NVM_DIR: '$HOME/.nvm'
$PREFIX: ''
$NPM_CONFIG_PREFIX: ''
$NVM_NODEJS_ORG_MIRROR: ''
$NVM_IOJS_ORG_MIRROR: ''
shell version: 'zsh 5.3 (x86_64-apple-darwin17.0)'
uname -a: 'Darwin 17.0.0 Darwin Kernel Version 17.0.0: Thu Aug 24 21:48:19 PDT 2017; root:xnu-4570.1.46~2/RELEASE_X86_64 x86_64'
OS version: Mac 10.13 17A405
curl: /usr/bin/curl, curl 7.54.0 (x86_64-apple-darwin17.0) libcurl/7.54.0 LibreSSL/2.0.20 zlib/1.2.11 nghttp2/1.24.0
wget: /usr/local/bin/wget, GNU Wget 1.19.1 built on darwin16.6.0.
git: /usr/local/bin/git, git version 2.14.2
grep: grep: aliased to grep  --color=auto --exclude-dir={.bzr,CVS,.git,.hg,.svn} (grep --color=auto --exclude-dir={.bzr,CVS,.git,.hg,.svn}), grep (BSD grep) 2.5.1-FreeBSD
awk: /usr/bin/awk, awk version 20070501
sed: illegal option -- -
usage: sed script [-Ealn] [-i extension] [file ...]
       sed [-Ealn] [-i extension] [-e script] ... [-f script_file] ... [file ...]
sed: /usr/bin/sed,
cut: illegal option -- -
usage: cut -b list [-n] [file ...]
       cut -c list [file ...]
       cut -f list [-s] [-d delim] [file ...]
cut: /usr/bin/cut,
basename: illegal option -- -
usage: basename string [suffix]
       basename [-a] [-s suffix] string [...]
basename: /usr/bin/basename,
rm: illegal option -- -
usage: rm [-f | -i] [-dPRrvW] file ...
       unlink file
rm: /bin/rm,
mkdir: illegal option -- -
usage: mkdir [-pv] [-m mode] directory ...
mkdir: /bin/mkdir,
xargs: illegal option -- -
usage: xargs [-0opt] [-E eofstr] [-I replstr [-R replacements]] [-J replstr]
             [-L number] [-n number [-x]] [-P maxprocs] [-s size]
             [utility [argument ...]]
xargs: /usr/bin/xargs,
nvm current: v6.11.3
which node: $NVM_DIR/versions/node/v6.11.3/bin/node
which iojs: iojs not found
which npm: $NVM_DIR/versions/node/v6.11.3/bin/npm
npm config get prefix: $NVM_DIR/versions/node/v6.11.3
npm root -g: $NVM_DIR/versions/node/v6.11.3/lib/node_modules
```
</details>

- `nvm ls` output:
<details>
<!-- do not delete the following blank line -->

```sh
       v0.12.15
         v4.5.0
         v6.9.1
->      v6.11.3
         v7.7.1
         v8.5.0
default -> 6.11.3 (-> v6.11.3)
defualt -> v6 (-> v6.11.3)
node -> stable (-> v8.5.0) (default)
stable -> 8.5 (-> v8.5.0) (default)
iojs -> N/A (default)
lts/* -> lts/boron (-> N/A)
lts/argon -> v4.8.4 (-> N/A)
lts/boron -> v6.11.4 (-> N/A)
```
</details>

- How did you install `nvm`? (e.g. install script in readme, homebrew): 
install script in reame: `curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.6/install.sh | bash`

- What steps did you perform?
`nvm uninstall v8.5`

- What happened?
nothing, output nothing

- What did you expect to happen?
uninstall v8.5

- Is there anything in any of your profile files (`.bashrc`, `.bash_profile`, `.zshrc`, etc) that modifies the `PATH`?

<!-- if this does not apply, please delete this section -->
- If you are having installation issues, or getting "N/A", what does `curl -I --compressed -v https://nodejs.org/dist/` print out?
<details>
<!-- do not delete the following blank line -->

```sh
```
</details>