PaulS:
You obviously haven't read any of the other threads that have asked the same question.
Obviously not. 
But it wasn't for lack of trying to find an answer.
The IDE is designed to NOT allow you to hide the use of a library from the sketch.
The sketch is parsed for include files. The sketch, all included header files, and the corresponding source files, are copied to another directory for compiling. From that directory, library-based include files are NOT available unless they are included in the sketch and copied to the build directory.
This is a terrific answer. Concise, and informative. I could quibble with the philosophy, but it is what it is and will run with it.
I appreciate your reply.