Clan up base64 redirects

[Highlander1694]

A lot of redirectors use base64 to obfuscate the link

http://example.com/aHR0cDovL3d3dy5nb29nbGUuY29t ➠ http://www.google.com

So https://ostermiller.org/calc/encode.html would become aHR0cHM6Ly9vc3Rlcm1pbGxlci5vcmcvY2FsYy9lbmNvZGUuaHRtbA==

base64 en/decoding is done easily with the atob() and btoa() functions in JavaScript.