Verify build on Windows 7/VS 2010.  Change to Apache license.  Specifica...

Verify build on Windows 7 / VS 2010.  Change to Apache license.  Specifically:

    -- Added WIN32 settings to Makefiles.
    -- SeExpression.cpp: Dereference vector rbegin() instead of end() to fix runtime error in prep().
    -- SeExprEdGrapher2d.cpp: Use float args in call to pow() to fix compile error
    -- SeExprSpecParser.y: Fix undefined snprintf
    -- SeExprSpecParserLex.l: Fix undefined math symbols
    -- imageSynth.cpp: Use vector to replace const array of dynamic size