Initial reorganisation

Moving library files to lib and examples & main executable into bin.
Now, things won't run, but we should be in more or less the right place
to make a gem work.
Put everything under a RubySynth module
Missing end in the previous commit
Gemfile & fixed

Gemfile added and example main class renamed so that the include of
'rubysynth' works on a case insensitive filesystem.
Readme to help out whoever comes next