Clarify possible values for CMAKE_CXX_STANDARD.

README.md

@@ -701,7 +701,7 @@ You will find that 3 tests fail at the end of the test suite.  It is safe to ign
 
 ### 2.17 Building with C++11 and other compilers
 
-Exiv2 uses the default compiler for your system.  Exiv2 v0.27 was written to the C++ 1998 standard and uses auto\_ptr.  The C++11 and C++14 compilers will issue deprecation warnings about auto\_ptr.  As _auto\_ptr support has been removed from C++17, you cannot build Exiv2 v0.27 with C++17 or later compilers._  Exiv2 v0.28 and later do not use auto\_ptr and will build with all compilers.
+Exiv2 uses the default compiler for your system.  Exiv2 v0.27 was written to the C++ 1998 standard and uses auto\_ptr.  The C++11 and C++14 compilers will issue deprecation warnings about auto\_ptr.  As _auto\_ptr support has been removed from C++17, you cannot build Exiv2 v0.27 with C++17 or later compilers._  Exiv2 v0.28 and later do not use auto\_ptr and will build with modern Standard C++ Compilers.
 
 To generate a build with C++11:
 
@@ -712,9 +712,9 @@ $ cmake .. -DCMAKE_CXX_STANDARD=11 -DCMAKE_CXX_FLAGS=-Wno-deprecated
 $ make
 ```
 
-The option -DCMAKE\_CXX\_FLAGS=-Wno-deprecated suppresses warnings from C++11 concerning auto\_ptr and other deprecated features.
+The option -DCMAKE\_CXX\_STANDARD=11 specifies the C++ Language Standard.  Possible values are 98, 11 or 14.
 
-**Caution:** Visual Studio users should not use -DCMAKE\_CXX\_STANDARD=11 or -DCMAKE\_CXX\_FLAGS=-Wno-deprecated.
+The option -DCMAKE\_CXX\_FLAGS=-Wno-deprecated suppresses warnings from C++11 concerning auto\_ptr and other deprecated features.  **Caution:** Visual Studio users should not use -DCMAKE\_CXX\_FLAGS=-Wno-deprecated.
 
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