HLS video playback (#182)

* HLS video playback

Signed-off-by: Adrian Lebioda <adrianlebioda@gmail.com>

* Add LibreJS compliance

* Locally host hls.js

* Notification about HLS under videos that support it

Signed-off-by: Adrian Lebioda <adrianlebioda@gmail.com>

* Use .contains() instead of .find() == None

* Make list of preferences constant

* Change headers_keys from Vector into Array

* Fix incorrect detecting of # in paths

* Remove trailing-slash-appending if statement

* Change HLS notification styling

Co-authored-by: spikecodes <19519553+spikecodes@users.noreply.github.com>

templates/subreddit.html

@@ -52,6 +52,10 @@
 			{% call utils::post_in_list(post) %}
 			{% endif %}
 			{% endfor %}
+			{% if prefs.use_hls == "on" %}
+			<script src="/hls.min.js"></script>
+			<script src="/playHLSVideo.js"></script>
+			{% endif %}
 			</div>
 
 			<footer>