Fix: update to reflect license change .txt --> .md (#3843)

License file was changed from LICENSE.txt to LICENSE.md in ffa861eb

isis/CMakeLists.txt

@@ -602,12 +602,12 @@ add_custom_target(clean_source COMMAND rm -rf "${CMAKE_BINARY_DIR}/*" "${CMAKE_I
 # Set up a few top level files for installation.
 EXECUTE_PROCESS(COMMAND cp -f  ${CMAKE_SOURCE_DIR}/IsisPreferences   ${CMAKE_BINARY_DIR})
 EXECUTE_PROCESS(COMMAND cp -rf ${CMAKE_SOURCE_DIR}/scripts           ${CMAKE_BINARY_DIR})
-EXECUTE_PROCESS(COMMAND cp -f  ${CMAKE_SOURCE_DIR}/../LICENSE.txt    ${CMAKE_BINARY_DIR})
+EXECUTE_PROCESS(COMMAND cp -f  ${CMAKE_SOURCE_DIR}/../LICENSE.md    ${CMAKE_BINARY_DIR})
 EXECUTE_PROCESS(COMMAND cp -rf ${CMAKE_SOURCE_DIR}/make              ${CMAKE_BINARY_DIR})
 
 # Copy the files on make install as well
 install(FILES     ${CMAKE_SOURCE_DIR}/IsisPreferences DESTINATION  ${CMAKE_INSTALL_PREFIX})
-install(FILES     ${CMAKE_SOURCE_DIR}/../LICENSE.txt  DESTINATION  ${CMAKE_INSTALL_PREFIX})
+install(FILES     ${CMAKE_SOURCE_DIR}/../LICENSE.md  DESTINATION  ${CMAKE_INSTALL_PREFIX})
 install(FILES     ${CMAKE_BINARY_DIR}/version         DESTINATION  ${CMAKE_INSTALL_PREFIX})
 install(DIRECTORY ${CMAKE_SOURCE_DIR}/scripts         DESTINATION  ${CMAKE_INSTALL_PREFIX})