[nicopaez] #2356 - Cache directive removed
[NicoPaez] #2356 - Cache config on homecontroller restored after spike
[john] #misc - Rails upgrade for security fixes.
[diego] #2472 - Set correct default donation frequency
[smarcet] #2516 - Do not allow American Express to be used if currency is not USD
Merge remote-tracking branch 'source/master' into allout
touching readme