Add some global functions to remote-content for clearing out cached

remote content.

@@ -36,7 +36,7 @@ const siteBaseQuery = async (args, api, options) => {
 
 export const sitePageSlice = createApi({
   reducerPath: 'pages',
-  tagTypes: ['Page'],
+  tagTypes: ['Site', 'Page'],
   keepUnusedDataFor: 60,
   refetchOnReconnect: true,
   refetchOnMountOrArgChange: true,
@@ -54,7 +54,10 @@ export const sitePageSlice = createApi({
       },
       providesTags: (result, err, args) => {
         const { site, page } = args
-        return [ { type: 'Page', id: { site, page } } ]
+        return [
+          { type: 'Site', id: site },
+          { type: 'Page', id: `${site}:${page}` },
+        ]
       },
     }),
   }),
@@ -83,5 +86,23 @@ export const getSiteBaseUrl = (name: string): string => {
   return configSlice.selectors.getSiteBaseUrl(store.getState(), name)
 }
 
+export const clearAll = () => {
+  return store.dispatch(sitePageSlice.util.invalidateTags([ 'Page' ]))
+}
+
+export const clearSite = (site: string) => {
+  return store.dispatch(sitePageSlice.util.invalidateTags([ { type: 'Site', id: site } ]))
+}
+
+export const clearPages = (site: string, ...pages: string) => {
+  return store.dispatch(sitePageSlice.util.invalidateTags(pages.map(page => ({ type: 'Page', id: `${site}/${page}` }) )))
+}
+
+export const prefetch = (site: string, ...pages: string) => {
+  return Promise.all(pages.map(page => {
+    return store.dispatch(sitePageSlice.util.prefetch('getPage', { site, page }, { force: true }))
+  }))
+}
+
 setSiteConfig({ name: 'direct' })