Redirect current version to GitHub releases

Our hoster uberspace noted that we're by far exceeding our traffic limit.
For now, redirect everything to GitHub releases.

downloads/.htaccess

@@ -0,0 +1,5 @@
+RewriteEngine On
+
+RewriteRule ^$ https://github.com/rg3/youtube-dl/releases
+RewriteRule latest(.*) /downloads/2016.06.03$1 [L,R=302]
+

downloads/2016.06.03/.htaccess

@@ -0,0 +1,5 @@
+RewriteEngine On
+
+RewriteRule ^$ https://github.com/rg3/youtube-dl/releases/tag/2016.06.03_tmp [R=302,L]
+RewriteRule ^(.+)$ https://github.com/rg3/youtube-dl/releases/download/2016.06.03_tmp/$1 [R=302,L]
+