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* All rights reserved.
*
* Contributor(s):
* Zechariah Perez, omni (at) zeriph (dot) com
*
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*/

    As the NULL macro is implementation defined and not all compilers will support
    the nullptr keyword, the default for null pointer values is to zeroize them, that is,
    the preferred way to initialize pointer types to the null value is to set them to the 0
    address over setting to NULL or nullptr. Example:

    int* val = 0;     <- preferred way
    int* val = NULL;    <- OK, but NULL could be anything, so not really "safe" if cross platform
    int* val = nullptr; <- OK and expresses intent better, but not all compilers support this

    We do not want to overuse macros through the library, but in this scenario, it is also
    preferable to avoid being able to do something like this:

    static const int nullptr = 0;
    int* val = &nullptr;

    &nullptr is not allowed in C++11 and additional checks would need to be in place to avoid this in
    C++11 compilers and not in previous editions; as well int* val = nullptr could have an implicit cast
    since you are referencing a named variable (nullptr), this is not the case in C++11 with the nullptr keyword.

    So to avoid all of this, we will give the user the option to choose (or define) their null pointer
    value. Defining OMNI_NULL_USE_NULLPTR sets the C++11 nullptr keyword while OMNI_NULL_USE_MACRO will use the
    implementation defined NULL macro, and if nothing, the default is to use 0. While the macro name
    OMNI_NULL_PTR is more verbose than 0/NULL/nullptr, it does express the intent better than just plain 0.

    Also note: this is -only- for pointer types used within the Omni library itself; the OMNI_NULL_PTR
    is not used for OS/system specific API's (like pthread_join, WideCharToMultiByte, etc.), instead
    the NULL macro is used (since that it what is defined/used in those specific docs).
*/