fixed debug assert on linux

src/escape_string.cpp

@@ -31,7 +31,6 @@ POSSIBILITY OF SUCH DAMAGE.
 */
 
 #include "libtorrent/pch.hpp"
-#include "libtorrent/assert.hpp"
 
 #include <string>
 #include <stdexcept>
@@ -40,6 +39,8 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <cctype>
 #include <algorithm>
 
+#include "libtorrent/assert.hpp"
+
 namespace libtorrent
 {
 	std::string unescape_string(std::string const& s)