---+ Package =TWiki::Configure::Checkers::Certificate::KeyChecker=
Configure GUI checker for Certificate Key items.

This checker validates files that contain private key files
such as for the S/MIME signatures and for the Tasks framework.

It must be subclassed for the various certificate types, as the requirements
are slightly different.


%TOC%

---++ ObjectMethod *check* <tt>($valueObject,$password) -> $errorString</tt>
Validates a Key item for the configure GUI
   * =$valueObject= - configure value object
   * =$password= - Optional password key name for this file

A lot of checking is done here to prevent mystery errors at runtime.

Returns empty string if OK, error string with any errors