Fix compiler warnings

[jmjatlanta]

This is a partial fix for #1246

Newer compilers throw many more warnings. These commits minimize the warnings by:

• moving destructor implementation to the implemenation file
• adding 2 -Wno-xxxx to the compiler options
• fixing many signed/unsigned comparison in tests

Moving the destructor to the implementation file still causes a warning, but it is at compile of the .cpp, not each time the .hpp is included.

Adding the compiler options squelches warnings that are caused by (1) boost and (2) a non-trivial copy.

There are still warnings about destructors throwing. I believe we should be using exit() instead of throwing, if we truly want to end the program, but these are sometimes within libraries. So I am unsure of the side effects (i.e. who all are using them, even outside the project).

[jmjatlanta]

Incorrect rebase goofed PR. Closing to create new one.