kde5 documentation

[Steven Friedrich]

When I open KDE Wallet, I selected Wallet Manager Handbook from the help menu.  
I got:
Documentation not Found
Jack Ostroff <ostroffjh at users.sourceforge.net>
Revision Frameworks 5.0 (2014-04-02)
The requested documentation was not found on your computer.
The documentation may not exist, or it may not have been installed with the 
application.

How can I install this documentation?