logic: Fixed log warnings of color scheme and edge

* fixed warnings for overriden node and edge colors
* fixed warnings for edges connecting the wrong node types
* removed tool tip from color scheme
* changed names in project setup screen

src/lib/settings/ProjectSettings.cpp

@@ -14,6 +14,7 @@ std::vector<std::string> ProjectSettings::getDefaultSourceExtensions()
 	defaultValues.push_back(".cpp");
 	defaultValues.push_back(".cxx");
 	defaultValues.push_back(".cc");
+	defaultValues.push_back(".c");
 	return defaultValues;
 }