feat: Config Option for other .scss/.sass import paths. (#346)

* Added config option to package.json to find imports

Scss imports in imports are often broken as the paths there may be absolute to node_modules (at least in the case of @Material packages).
To fix this, there is now a config option in package.json: vue.css.loaderOptions.sass.includePaths (array of Strings)

* replaced tab caracter with spaces

* fixed indention

Author: marvinside

packages/vue-sass/vue-sass.js

@@ -18,15 +18,27 @@ function resolveImport (dependencyManager) {
       let currentDirectory = path.dirname(prev === 'stdin' ? this.options.outFile : prev)
       resolvedFilename = path.resolve(currentDirectory, url)
     }
+    const importPaths = [ resolvedFilename ]
+    const pjson = require("package.json") // can not be moved outside. Reqired here to get the package.json of the project that is being run
 
-    resolvedFilename = discoverImportPath(resolvedFilename)
-    if (resolvedFilename === null) {
+    try {
+      // get the package.json config option and create paths for the requested file.
+      pjson.vue.css.loaderOptions.sass.includePaths.forEach( (str) => {
+        importPaths.push(path.resolve(str, url))
+      })
+    } catch (e) {
+      // Ignore error. package.json option is not set.
+    }
+
+    const resolvedNames = importPaths.map( discoverImportPath ).filter((fileName) => fileName !== null && typeof fileName !== "undefined");
+
+    if (resolvedNames.length < 1) {
       done(new Error('Unknown import (file not found): ' + url))
     } else {
-      dependencyManager.addDependency(resolvedFilename)
+      dependencyManager.addDependency(resolvedNames[0])
 
       done({
-        file: resolvedFilename,
+        file: resolvedNames[0],
       })
     }
   }