adding a to_bool method in initializers to convert a string to boolean
saving down upfront sub type if sign up is an upfront
dropping upfront boolean column from subs table
method to obtain term from chargify for an upfront and save it down
saving down term if sign up is an upfront
Merge pull request #57 from SunnyIzr/persisting-upfront-term-upon-creation

Persisting upfront term upon creation