Update issue templates

.github/ISSUE_TEMPLATE/remove-channel.md

@@ -0,0 +1,17 @@
+---
+name: Remove Channel
+about: Request to remove a channel from the playlist
+title: 'Remove: xxx'
+labels: DMCA
+assignees: ''
+
+---
+
+<!-- Please fill out the information in this issue template so that we can
+efficiently process your request -->
+
+<!-- IMPORTANT: An issue may contain a request for only one channel, otherwise it will be closed -->
+
+***Channel Name:*** xxx
+***DMCA Notice (link):*** xxx
+***Notes (optional):*** xxx