Add PDF compatible HTML helper wrappers.
Add PDF compatible HTML helper wrappers.

The rails helpers like number_with_precision do escape some characters we
do want to directly use in PDF. This unescapes them again.

hauledev/bookyt,gaapt/bookyt,gaapt/bookyt,silvermind/bookyt,xuewenfei/bookyt,silvermind/bookyt,huerlisi/bookyt,silvermind/bookyt,wtag/bookyt,hauledev/bookyt,gaapt/bookyt,silvermind/bookyt,gaapt/bookyt,wtag/bookyt,hauledev/bookyt,hauledev/bookyt,xuewenfei/bookyt,wtag/bookyt,xuewenfei/bookyt,huerlisi/bookyt,huerlisi/bookyt