Add auth support (#21)

* Updates

* Update

* Update

* Update

* Update

* Yarn sometimes prefers npmrc, so use same token

* Description

* Update readme

* Feedback

* Add type

* new toolkit and scoped registries

* npmrc in RUNNER_TEMP

* Dont always auth

* Try exporting blank token

* Get auth working for now pending runner changes

* Fix string interpolation for auth token.

* Don't export both userconfigs

* Update authutil.js

* Add single quotes for authString

* Fix the registry string.

* Use userconfig and append trailing slash

* Keep in root of repo

* Try just adding auth token

* Remove auth token

* Try changes again

* Add tests

* Npm and GPR samples

* Add types

node_modules/cross-spawn/lib/util/resolveCommand.js

@@ -0,0 +1,47 @@
+'use strict';
+
+const path = require('path');
+const which = require('which');
+const pathKey = require('path-key')();
+
+function resolveCommandAttempt(parsed, withoutPathExt) {
+    const cwd = process.cwd();
+    const hasCustomCwd = parsed.options.cwd != null;
+
+    // If a custom `cwd` was specified, we need to change the process cwd
+    // because `which` will do stat calls but does not support a custom cwd
+    if (hasCustomCwd) {
+        try {
+            process.chdir(parsed.options.cwd);
+        } catch (err) {
+            /* Empty */
+        }
+    }
+
+    let resolved;
+
+    try {
+        resolved = which.sync(parsed.command, {
+            path: (parsed.options.env || process.env)[pathKey],
+            pathExt: withoutPathExt ? path.delimiter : undefined,
+        });
+    } catch (e) {
+        /* Empty */
+    } finally {
+        process.chdir(cwd);
+    }
+
+    // If we successfully resolved, ensure that an absolute path is returned
+    // Note that when a custom `cwd` was used, we need to resolve to an absolute path based on it
+    if (resolved) {
+        resolved = path.resolve(hasCustomCwd ? parsed.options.cwd : '', resolved);
+    }
+
+    return resolved;
+}
+
+function resolveCommand(parsed) {
+    return resolveCommandAttempt(parsed) || resolveCommandAttempt(parsed, true);
+}
+
+module.exports = resolveCommand;