Started replacing std::function with custom lambda wrapper
Added rudimentary lambda implemnetation (memory has to be done)
updated samples to use sdli::util::Lambdas / sdli::Callbacks (Lambdas are just a generalization)
disable of std::setbuf in samples/
updated README.md
dev-help: added stubbing (clang)
Array impl
Default werte for axis mapping (normalize=1.0f)
add device:currentcontext
moved array impl to util/
rename SDLI_STUB to STUB
updated cmake to use ccache (rather than defining it in qtcreator)