Rename A:BF.css to A-BF.css

To fix "difficulties" when using this repository on a windows based OS (doesn't allow colons in filenames)
Rename A:BF.html to A-BF.html

To fix "difficulties" when using this repository on a windows based OS (doesn't allow colons in filenames)
Update sheet.json

To fix "difficulties" when using this repository on a windows based OS (doesn't allow colons in filenames)
Added a sheet build number and date to the top of the help section
Merge branch 'master' into phb-release