IconComboBox v1.02

Just to let everyone know that v1.02 of IconComboBox has been released. Updates for this version include:

• Updated copyright details.
• Replaced all occurrences of NULL with nullptr throughout the codebase.
• Updated the code to clean compile on VC 2010 to VC 2015. The code now requires VC 2010 at a minimum.
• Reworked the CSmallIconComboBox and CLargeIconComboBox classes to use a new CIconComboBox base class which supports arbitrary sized icons.