added stripe functions around invoice and subscriptions
provide return values for add/replace card, and renamed update_card to replace_card
add return value for stripe subscription functions
added more parameters for rollbar logging
added a timestamp template filter
added check for valid invoice before attempting to pay invoice
add missing rollbar import
Merge pull request #108 from talentral/master

a bunch of stuff for stripe
commented out debugging stuff; just directlyr report exception to rollbar
determine live_mode for stripe based on setting as well as environment
Merge pull request #109 from talentral/master

live_mode stuff for stripe
add missing 0 to JCB card
Merge pull request #110 from talentral/master

add missing 0 to JCB card
split up accounts utils into general, debug, and lookup utils
added timezone lookup stuff