Eigenface and Full-Eigenface algorithms incompatible

Originally, these toolchains were supposed to share most of the algorithms, but now we realise this is not possible since the input data formats are different.

For example, in the simple eigenface toolchain, image objects are of type uint8, while in the advanced version, image inputs are preprocessed (cropped, corrected, etc) and, therefore are of type float64.

We must fix this situation by creating 2 versions of the concerned algorithms.