Abolish compilation server

This PR removes the compilation server.  The move is justified by the following reasons.

* there seem to be some issues related to compilation server (see #308)
* compilation server adds complexity, but it is not widely being used if any
* if we are to optimize the completion mode, it would be easier to create a separate entry point (other than ```bin/jsx```) _dedicated_ to the purpose than trying to speed up the generic interface of the compiler
* the only test that depended on the compilation server was ```t/007.mode-parse.t``` and dissolving the dependency increased the time need for the test to complete from 0m10s to 1m30s.  It sounds like a drawback but actually is not a problem since the time required to run the whole test-suite is much longer