Peter M. Groen / openbr

With this, we will not have to accumulate the file metadata during enroll
which will help with memory use on large jobs.

Functions actually using the return type (gui/classifier.cpp, and gallerytoolbar.cpp)
updated to avoid using it directly. In gallerytoolbar.cpp, drop support for
implicit enrollment to a .gal file.

Basically, description() now relies on firstAvailablePropertyIndex being
set correctly, and this is done in Object::init(file). If an object is
not created via the plugin system, Object::init(file) is never called.

Also, description is now called as part of smartCopy, which is of course
called when project() const is called on a timeVarying transform.

Merged!

Update these algorithms to draw all detected faces on the same image, and
only display that image once. Also, modify ShowFaceDetection to discard
matrices that have already been displayed.

This is unsafe since in some scenarios, the window is already part of
an event loop.

A stopwatch and profiler to get time data for specified openbr transforms

Better support for serializing algorithms in memory

Refactor handling of simplified pointer in AlgorithmCore
Remove parameter from serialize, it's literally impossible for it to do
anything useful
Remove spaces after * and & (saving valuable bytes of source code).

Also, more careful memory management of the simplified transform in
AlgorithmCore

Instead of having a parameter to force serialization of loadStores,
introduce a recursive method for simplifiying transform trees. Transforms
which are only useful during load/training can now remove themselves from
the tree via Transform * simplify, returning e.g. their child transform
instead of themselves when possible.

This avoids the issue of LoadStore transforms refusing to serialize
themselves onto an input stream during multi-process enrollment, since
they are just removed from the tree.

For consistency with other supported compilers, enable a warning about
unused parameters at warning level 3 in visual studio.

By default this warning is at level 4, but using level 4 isn't really
feasible since a ton of warnings are generated for Qt header files.

Rather than saving the Transform and distance strings of an algorithm
together, in stored files, save the transform and distance descriptions
separately. Also introduce an enum allowing for the serialization of
algorithms which use gallery comparison transforms, rather than distances
as their comparison function.

Update pre-trained algorithms, this only requires updating the algorithm
files themselves, transforms saved via LoadStore are unaffected.

This gives us robustness to one type of model file compatibility break, if
e.g. the FaceRecognitionRegistration abbreviation is changed, any results
of <FaceRecognitionRegistration> that were previously saved to disk are
not invalidated (although any changes to FaceRecognitionRegistration will
not be reflected until the model is re-trained).