Fix the documentation to say what it really does. Bug #9638

Modules/TestForANSIForScope.cmake

 # - Check for ANSI for scope support
-# Check if the compiler supports std:: on stl classes.
+# Check if the compiler restricts the scope of variables declared in a for-init-statement to the loop body.
 #  CMAKE_NO_ANSI_FOR_SCOPE - holds result
 #
 

Modules/TestForANSIStreamHeaders.cmake

 # - Test for compiler support of ANSI stream headers iostream, etc.
-# check if we they have the standard ansi stream files (without the .h)
+# check if the compiler supports the standard ANSI iostream header (without the .h)
 #  CMAKE_NO_ANSI_STREAM_HEADERS - defined by the results
 #
 

Modules/TestForSSTREAM.cmake

-# # - Test for std:: namespace support
-# check if the compiler supports std:: on stl classes
+# - Test for compiler support of ANSI sstream header
+# check if the compiler supports the standard ANSI sstream header
 #  CMAKE_NO_ANSI_STRING_STREAM - defined by the results
 #