Fix homepage, icon and screenshot URLs referened in CMakeLists.txt

[jcfr]

Update CMakeLists.txt to fix homepage, icon and screenshot URLs:

Slicer-ThicknessMap/CMakeLists.txt

Lines 7 to 13 in 578b9e0

	set(EXTENSION_HOMEPAGE "https://www.slicer.org/wiki/Documentation/Nightly/Extensions/ThicknessMap")
	set(EXTENSION_CATEGORY "Shape Analysis")
	set(EXTENSION_CONTRIBUTORS "Muhammed Fatih Talu (Inonu University)")
	set(EXTENSION_DESCRIPTION "Calculation bone thickness mapping")
	set(EXTENSION_ICONURL "http://www.example.com/Slicer/Extensions/ThicknessMap.png")
	set(EXTENSION_SCREENSHOTURLS "http://www.example.com/Slicer/Extensions/ThicknessMap/Screenshots/1.png")
	set(EXTENSION_DEPENDS "NA") # Specified as a list or "NA" if no dependencies