Fix our own compiler warnings #1677
This solves the "Internal warnings" part of #1658
A *full clean build was done on:
*The wallet was only build on Windows
All warnings were analysed and ones which were caused by us (i.e not third party ones) should now be fixed, with an exception detailed at the end. These include:
warning C4996: 'localtime': This function or variable may be unsafe. Consider using localtime_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
The only warnings left are:
We recently deprecated them, so wasn't sure if we should suppress the warnings, as it will be nice to have a constant reminder about them so that they don't get forgotten.