Create tokens
Modify template
Implemented Cancellation functions
	- getting Cancellation record
	- email template & token
Added Cancellation table to Booking View
Added Contribution table to Booking view
Cleaned code - remove debugging line
Merge pull request #6 from chanunc/master

Email tokens and template, Cancellation and Contribution view
load default date on calendar from the first slot selected when editing a booking
Fixed getting wrong booking detail
make sure we compare integer
Changed the label from ad-hoc charges to additional charges
Changed the text for ad-hoc charges
Fixed
add convert label into name field
Removed name from the adhoc charges form and page as it use in the system
show a link to create a new additional charges item if there is no additional charges item in the system
Rename ad-hoc charges to Additional charges
load adhoc charges when editing booking