ExternalProject Fix INDEPENDENT_STEP_TARGETS option

The part of code that generates the options to be accepted by the EP
functions expects the comment to be on the same line as the option
ExternalProject: Fix indentation
ExternalProject: Add unit tests for NO_DEPENDS and INDEPENDENT_STEP_TARGETS
Merge topic 'CMakeParseArguments_EmptyArgs' into ExternalProject-independent-step-targets

Conflicts:
	Tests/RunCMake/CMakeLists.txt
Merge topic 'ExternalProject-independent-step-targets' into next

a7128d7 Merge topic 'CMakeParseArguments_EmptyArgs' into ExternalProject-independent-step-targets
ac1abf6 ExternalProject: Add unit tests for NO_DEPENDS and INDEPENDENT_STEP_TARGETS
720c1a8 ExternalProject: Fix indentation
1f70d2c ExternalProject Fix INDEPENDENT_STEP_TARGETS option