[Java] Update README.md for distribution note.

Author: mjpt777

README.md

@@ -90,11 +90,11 @@ Jars for the executable, source, and javadoc for the various modules can be foun
  sbe-tool/build/libs
  sbe-all/build/libs
 
-An example to execute a Jar from command line:
+An example to execute a Jar from command line using the 'all' jar which includes the Agrona dependency:
 
- java -Dsbe.generate.ir=true -Dsbe.target.language=Cpp -Dsbe.target.namespace=sbe -Dsbe.output.dir=include/gen -Dsbe.errorLog=yes -jar sbe-tool/build/libs/sbe-tool-1.7.0-all.jar my_sbe_input.xml
+ java -Dsbe.generate.ir=true -Dsbe.target.language=Cpp -Dsbe.target.namespace=sbe -Dsbe.output.dir=include/gen -Dsbe.errorLog=yes -jar sbe-all/build/libs/sbe-all-1.7.0-SNAPSHOT.jar my_sbe_input.xml
 
-Note: The Jars in directory `build/libs` do not contain `META-INF/MANIFEST.MF` and the error *"no main manifest attribute"* will occur when trying to execute it.
+**Note:** The Jars in directory `build/libs` do not contain `META-INF/MANIFEST.MF` and the error *"no main manifest attribute"* will occur when trying to execute it.
 
 C++ Build using CMake
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