Odd... it works in pure IRB but on in Rails console...

````
[t27duck@mobi-lappy zerofill]$ irb
irb(main):001:0> require "zero_fill"
=> true
irb(main):002:0> myDates = {
irb(main):003:1* Date.parse("2013-07-29") => 10, #Monday
irb(main):004:1* Date.parse("2013-07-31") => 7,  #Wednesday
irb(main):005:1* Date.parse("2013-08-02") => 3   #Friday
irb(main):006:1> }
=> {#<Date: 2013-07-29 ((2456503j,0s,0n),+0s,2299161j)>=>10, #<Date: 2013-07-31 ((2456505j,0s,0n),+0s,2299161j)>=>7, #<Date: 2013-08-02 ((2456507j,0s,0n),+0s,2299161j)>=>3}
irb(main):007:0> ZeroFill.new(myDates).by_date
=> {#<Date: 2013-07-29 ((2456503j,0s,0n),+0s,2299161j)>=>10, #<Date: 2013-07-30 ((2456504j,0s,0n),+0s,2299161j)>=>0, #<Date: 2013-07-31 ((2456505j,0s,0n),+0s,2299161j)>=>7, #<Date: 2013-08-01 ((2456506j,0s,0n),+0s,2299161j)>=>0, #<Date: 2013-08-02 ((2456507j,0s,0n),+0s,2299161j)>=>3}
````