Fix PS call

Author: glibas

appveyor.yml

@@ -37,7 +37,8 @@ install:
   - npm i nan@%nan_version%
   - npm install -g node-pre-gyp@%pre_gyp_version%
   - npm install -g node-pre-gyp-github@%pre_gyp_github_version%
-  - ps: "//registry.npmjs.org/:_authToken=$env:npm_auth_token`n" | out-file "$env:userprofile\.npmrc" -Encoding ASCII
+  - ps:  >- 
+        "//registry.npmjs.org/:_authToken=$env:npm_auth_token`n" | out-file "$env:userprofile\.npmrc" -Encoding ASCII
 
 build_script:
   - node-pre-gyp configure