port meta examples to new API

[karlnapf]

All meta examples should

• use the generic put and get methods rather than custom getters setters
• use factory methods, instead of parametrised constructors, to create new objects, load files, etc (and subsequent put/get calls). Pls use the kwargs feature (see meta_api/kwargs.sg
• dont use types apart from the base types: Machine, Kernel, Labels (not RegressionLabels, etc), Features

See https://github.com/shogun-toolbox/shogun/blob/develop/examples/meta/src/binary/kernel_support_vector_machine.sg for a fully ported example

Note that this might involve creating new factory methods.

[karlnapf]

This is still open, there are still some

• constructor calls ( to be replaced by factory calls)
• specialized method calls (should be refactored to put/get or otherwise)

[karlnapf]

I think this should be almost done?