move plugin management from ui-core to server-core

Summary:
Follow up of D32665064, this diff moves all plugin management logic from flipper-ui to flipper-server. Things like downloading, installing, querying new plugins.

Loading plugins is handled separately in the next diff.

Reviewed By: nikoant

Differential Revision: D32666537

fbshipit-source-id: 9786b82987f00180bb26200e38735b334dc4d5c3

desktop/flipper-ui-core/src/utils/pathUtils.tsx

@@ -16,6 +16,9 @@ import fs from 'fs';
 import config from '../fb-stubs/config';
 import {getRenderHostInstance} from '../RenderHost';
 
+/**
+ * @deprecated
+ */
 export function getStaticPath(
   relativePath: string = '.',
   {asarUnpacked}: {asarUnpacked: boolean} = {asarUnpacked: false},
@@ -31,6 +34,9 @@ export function getStaticPath(
     : absolutePath;
 }
 
+/**
+ * @deprecated
+ */
 export function getChangelogPath() {
   const changelogPath = getStaticPath(config.isFBBuild ? 'facebook' : '.');
   if (fs.existsSync(changelogPath)) {