changes to gurlsWrapper and train-test beta functions

it is now possible to set ownership of a GurlsOptionsList pointer when
passing it to a wrapper through LoadOpt
added overloaded LoadOpt to wrappers to load a GurlsOptionsList from
file
test function changed internally in order to minimize memory usage, and
to match changes to wrapper
train function now returns a GurlsOptionList pointer
changes to traintest_demo to show new usage
updated Manuals and READMEs, removed TESTs

build information are now updated in both READMEs and manual
updated "Designing and Implementing a new functionality" manual section
minor fixes to examples shown in the manuals
removed "Test" manual section (not working), and removed
GURLSPP_BUILD_TEST option from gurls++ CMakeLists