Add missing files

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/tests/frontend/scanner.cpp

@@ -0,0 +1,29 @@
+/*
+Copyright (c) 2013 Microsoft Corporation. All rights reserved.
+Released under Apache 2.0 license as described in the file LICENSE.
+
+Author: Leonardo de Moura
+*/
+#include <sstream>
+#include "scanner.h"
+#include "test.h"
+using namespace lean;
+
+static void tst1() {
+    char tst[] = "fun(x: pi A : Type, A -> A), (* (* test *) *) x+1 = 2.0 λ";
+    std::istringstream in(tst);
+    scanner s(in);
+    while (true) {
+        scanner::token t = s.scan();
+        if (t == scanner::token::Eof)
+            break;
+        std::cout << t << " ";
+    }
+    std::cout << "\n";
+}
+
+int main() {
+    continue_on_violation(true);
+    tst1();
+    return has_violations() ? 1 : 0;
+}

src/util/sexpr/CMakeLists.txt

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+add_library(sexpr sexpr.cpp sexpr_funcs.cpp format.cpp options.cpp)
+target_link_libraries(sexpr ${LEAN_LIBS})