updated global ignores to ignore temporary and intermediate files
updated global ignores to ignore build folders
reworked release script to work with SVN and to be self-contained
Updated colourised headers to match code
Removed all exception specifications in line with C++11 specification
accidentally added spurious project files
incremented the version number, this is now the development v3.15
Added support for Visual Studio 2017 builds, removed Visual Studio 6
clarified description especially for cloning subclass
use the new int-to-string conversions throughout
