Fix 2 small errors to compile on MSVC 2017

[Florent2305]

All is in the title :)

[astamm]

Thanks. All good for me. When should we include ANIMA***_EXPORT macro in class definitions?

[Florent2305]

Export definitions apply to compiled symbols (in the classic C/C++ compilation pipeline).

By definition, templates do not generate compiled symbols.
It's only when the template instantiation (not the template itself) is compiled will it generate compiled symbols.

In summarize:

• No export definitions for templates
• Export definitions for symboles you want to access throw a DLL (symbols: class, variables, function template instaciation)

[ecaruyer]

All good, thanks @Florent2305 !