Updated logs viewer component

- now by default last 50 lines are showed
- added copy to clipboard button
- added loading spinner to indicate to users when the logs are loading

app.get('/api/logs') is now app.post to allow for additional parameters (such as lines to retrieve)

src/app/posts.services.ts

@@ -234,8 +234,8 @@ export class PostsService implements CanActivate {
         return this.http.post(this.path + 'getVideoInfos', {fileNames: fileNames, type: type, urlMode: urlMode}, this.httpOptions);
     }
 
-    getLogs() {
-        return this.http.get(this.path + 'logs', this.httpOptions);
+    getLogs(lines = 50) {
+        return this.http.post(this.path + 'logs', {lines: lines}, this.httpOptions);
     }
 
     isPinSet() {