Fix comment count extraction due to 'K/M' postfixes

YouTube now displays 2K comments instead of 2359, for instance

youtube/__init__.py

@@ -39,7 +39,10 @@ def commatize(num):
     if num is None:
         return ''
     if isinstance(num, str):
-        num = int(num)
+        try:
+            num = int(num)
+        except ValueError:
+            return num
     return '{:,}'.format(num)
 
 def timestamp_replacement(match):

youtube/templates/watch.html

@@ -670,7 +670,7 @@ <h2 class="title">{{ title }}</h2>
             <div class="comments-area-outer comments-disabled">Comments disabled</div>
         {% else %}
             <details class="comments-area-outer" {{'open' if settings.comments_mode == 1 else ''}}>
-                <summary>{{ comment_count|commatize }} comment{{'s' if comment_count != 1 else ''}}</summary>
+                <summary>{{ comment_count|commatize }} comment{{'s' if comment_count != '1' else ''}}</summary>
                 <section class="comments-area-inner comments-area">
                     {% if comments_info %}
                         {{ comments.video_comments(comments_info) }}

youtube/yt_data_extract/watch_extraction.py

@@ -363,12 +363,12 @@ def _extract_watch_info_mobile(top_level):
             comment_count_text = extract_str(deep_get(comment_info,
                 'header', 'commentSectionHeaderRenderer', 'countText'))
         if comment_count_text == 'Comments':    # just this with no number, means 0 comments
-            info['comment_count'] = 0
+            info['comment_count'] = '0'
         else:
-            info['comment_count'] = extract_int(comment_count_text)
+            info['comment_count'] = extract_approx_int(comment_count_text)
         info['comments_disabled'] = False
     else:   # no comment section present means comments are disabled
-        info['comment_count'] = 0
+        info['comment_count'] = '0'
         info['comments_disabled'] = True
 
     # check for limited state