fix(auto-import): invalidate component options cache (#31)

Author: IlCallo

lib/loader.auto-import.js

@@ -72,10 +72,10 @@ module.exports = function (content) {
 
       const code = `\nimport {${comp}${hasComp === true && hasDir === true ? ',' : ''}${dir}} from 'quasar'\n` +
         (hasComp === true
-          ? `component.options.components = Object.assign(component.options.components || {}, {${comp}})\n`
+          ? `component.options.components = Object.assign(Object.create(component.options.components || null), component.options.components || {}, {${comp}})\n`
           : '') +
         (hasDir === true
-          ? `component.options.directives = Object.assign(component.options.directives || {}, {${dir}})\n`
+          ? `component.options.directives = Object.assign(Object.create(component.options.directives || null), component.options.directives || {}, {${dir}})\n`
           : '')
 
       return index === -1