Fixed letter-spacing
Merge pull request #220 from Useful-Innovation/davids-fixes

Fixed letter-spacing
Changed layout on create_invoice

*You can now see the diff between the offered price and the total price
for work and the diff between offered price and the total price.
*added a function to calculate the total in-price of a purchase
*added a function to calculate the total price for the hours worked
Merge pull request #221 from Useful-Innovation/changes

Changed layout on create_invoice