Improve exception safety with smart pointers

[elfring]

Would you like to wrap any pointers with the class template “std::unique_ptr”?

Update candidates:

• AddDatabaseField
• InfoPage
• NotesDocuments

[CSMathematics]

I find unique and shared pointers very interesting. But first I need to test them because I ve never used them before. What is your idea of using them?

[elfring]

:thought_balloon: Would you like to take the C++ guideline “R.11: Avoid calling new and delete explicitly” better into account?

[CSMathematics]

I see that is really helpful and promissing. I think I'm going to be using smart pointers from now on more often.

[elfring]

By the way: :thought_balloon: The management of parent-child relationships needs further development attention (as usual).