dynamically populate vue material table
<md-table v-model="previewData" md-sort="name" md-sort-order="asc" md-fixed-header>
<md-table-row slot="md-table-row" slot-scope="{ item }">
<md-table-cell
v-for="head in headers"
key="head"
:md-label="head"
:md-sort-by="head"
>
{{ item[head] }}
</md-table-cell>
</md-table-row>
</md-table>