The attached patch adds a package definition for Kawa. The 
synopsis and description differ from what guix lint suggests, but 
I'm not convinced that the suggested synopsis and description are 
better than what I have.

The suggested synopsis is "Java framework and implementation of 
Scheme, Elisp, and more", and the suggested description is "GNU 
Kawa is an implementation of the Scheme programming language that 
is built on top of the Java platform.  It is thus conveniently 
integrated with Java and benefits from this by having a compiler, 
optional static typing, and so on.  Kawa also serves as a 
framework for implementing other programming languages on the Java 
platform.  Included in Kawa is qexo, a partial implementation of 
XQuery in Java."