Put the current git commit's short hash in generated programs (again).

This commit restores changes I made in commit 2365217 that Xuejun Yang
undid in commit 4368520.

src/OutputMgr.cpp

@@ -362,9 +362,9 @@ OutputMgr::OutputHeader(int argc, char *argv[], unsigned long seed)
 		out << " * This is a RANDOMLY GENERATED PROGRAM." << endl;
 		out << " *" << endl;
 		out << " * Generator: " << PACKAGE_STRING << endl;
-	#ifdef SVN_VERSION
-		out << " * svn version: " << SVN_VERSION << endl;
-	#endif
+#ifdef GIT_VERSION
+		out << " * Git version: " << GIT_VERSION << endl;
+#endif
 		out << " * Options:  ";
 		if (argc <= 1) {
 			out << " (none)";

src/RandomProgramGenerator.cpp

@@ -107,10 +107,9 @@ static void
 print_version(void)
 {
 	cout << PACKAGE_STRING << endl;
-#ifdef SVN_VERSION
-	cout << "svn version: " << SVN_VERSION << endl;
+#ifdef GIT_VERSION
+	cout << "Git version: " << GIT_VERSION << endl;
 #endif
-	// XXX print svn rev!
 	// XXX print copyright, contact info, etc.?
 }