example: intro an emscripten wrapper around hello world

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
example: intro an emscripten wrapper around fibonacci

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
examples: intro a README file to emscripten examples

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
emscripten: add general features to lib

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>