warnings: don't spam with warning for missing field initializer

This allows the initialization of structs and objects to the default values in c++ using {} without warnings:

```
Classname::Classname() :
    _foostruct1({}),
    _blastruct2({})
{
}
```
instead of using the C-style memset.

Here are some explanations:
http://stackoverflow.com/questions/1538943/why-is-the-compiler-throwing-this-warning-missing-initializer-isnt-the-stru?answertab=active#tab-top