v0.4.15

#264 Fingerprint favicon by Gaurav0
#255 Link to GH release page of current version by pangratz
#249 Changed GH logo to be a bg image in css rather than inline image by brianally
#248 Two way address bar by pangratz
#243 Added wrapper around iframe to make it responsive. by brianally
#240 Add helper blueprint by knownasilya
#239 Loud Save Error by Gaurav0
#235: Style Twiddles Table by Gaurav0
#233 Implement logout on /twiddles route by pangratz