added basic subscriptions support for playlists and channels

update youtube-dl binary on windows

updated favicon to the new icon

src/app/dialogs/subscribe-dialog/subscribe-dialog.component.ts

@@ -0,0 +1,69 @@
+import { Component, OnInit } from '@angular/core';
+import { MatSnackBar, MatDialogRef } from '@angular/material';
+import { PostsService } from 'app/posts.services';
+
+@Component({
+  selector: 'app-subscribe-dialog',
+  templateUrl: './subscribe-dialog.component.html',
+  styleUrls: ['./subscribe-dialog.component.scss']
+})
+export class SubscribeDialogComponent implements OnInit {
+  // inputs
+  timerange_amount;
+  timerange_unit = 'days';
+  download_all = true;
+  url = null;
+  name = null;
+
+  // state
+  subscribing = false;
+
+  time_units = [
+    'day',
+    'week',
+    'month',
+    'year'
+  ]
+
+  constructor(private postsService: PostsService,
+              private snackBar: MatSnackBar,
+              public dialogRef: MatDialogRef<SubscribeDialogComponent>) { }
+
+  ngOnInit() {
+  }
+
+  subscribeClicked() {
+    if (this.url && this.url !== '') {
+      // timerange must be specified if download_all is false
+      if (!this.download_all && !this.timerange_amount) {
+        this.openSnackBar('You must specify an amount of time');
+        return;
+      }
+      this.subscribing = true;
+
+      let timerange = null;
+      if (!this.download_all) {
+        timerange = 'now-' + this.timerange_amount.toString() + this.timerange_unit;
+      }
+
+      this.postsService.createSubscription(this.url, this.name, timerange).subscribe(res => {
+        this.subscribing = false;
+        if (res['new_sub']) {
+          this.dialogRef.close(res['new_sub']);
+        } else {
+          if (res['error']) {
+            this.openSnackBar('ERROR: ' + res['error']);
+          }
+          this.dialogRef.close();
+        }
+      });
+    }
+  }
+
+  public openSnackBar(message: string, action = '') {
+    this.snackBar.open(message, action, {
+      duration: 2000,
+    });
+  }
+
+}