Used *.c extension and lower case dir name

diff --git a/examples/Graphics/Printing/MultipleWindowsText/source/main.cpp b/examples/graphics/printing/multiple-windows-text/source/main.cpp
similarity index 100%
rename from examples/Graphics/Printing/MultipleWindowsText/source/main.cpp
rename to examples/graphics/printing/multiple-windows-text/source/main.cpp