[Glitch] Display customized mascot in web UI

Port relevant parts of 9d4541c612 to glitch-soc

app/javascript/flavours/glitch/features/drawer/index.js

@@ -23,7 +23,7 @@ import DrawerResults from './results';
 import DrawerSearch from './search';
 
 //  Utils.
-import { me } from 'flavours/glitch/util/initial_state';
+import { me, mascot } from 'flavours/glitch/util/initial_state';
 import { wrap } from 'flavours/glitch/util/redux_helpers';
 
 //  Messages.
@@ -127,7 +127,7 @@ class Drawer extends React.Component {
             <Composer />
             {multiColumn && (
               <div className='drawer__inner__mastodon'>
-                <button className='mastodon' onClick={onClickElefriend} />
+                {mascot ? <img alt='' draggable='false' src={mascot} /> : <button className='mastodon' onClick={onClickElefriend} />}
               </div>
             )}
           </div>}

app/javascript/flavours/glitch/util/initial_state.js

@@ -24,6 +24,7 @@ export const searchEnabled = getMeta('search_enabled');
 export const maxChars = (initialState && initialState.max_toot_chars) || 500;
 export const invitesEnabled = getMeta('invites_enabled');
 export const version = getMeta('version');
+export const mascot = getMeta('mascot');
 export const isStaff = getMeta('is_staff');
 
 export default initialState;