Fix MSVC export declarations in SINQ library.

This allows the tests to compile.
Refs #7505
Increase version number of Python LoadSINQ algorithm to 2

There is currently a bug with the FileLoaderRegistry when a Python
algorithm has the same name & version as a C++ algorithm that is defined
as a loader. The Python alg silently overwrites the C++ one and crashes
the file loader search. For now call this version 2 to avoid this.
Refs #7505