Added various SSL utility functions

These new functions are mostly SSL type objects that converted into
ASCII strings (which much be free()'d)

- htp_sslutil_subject_tostr() : creates string from the ssl subject
- htp_sslutil_issuer_tostr()
- htp_sslutil_notbefore_tostr()
- htp_sslutil_notafter_tostr()
- htp_sslutil_sha1_tostr()
- htp_sslutil_serial_tostr()
- htp_sslutil_cipher_tostr()
- htp_sslutil_cert_tostr()
- htp_sslutil_x509_ext_tostr()

CMakeLists.txt

@@ -185,7 +185,8 @@ set(LIBEVHTP_EXTERNAL_LIBS
 set (LIBEVHTP_SOURCE_FILES
     evhtp.c
     numtoa.c
-    parser.c)
+    parser.c
+    sslutils.c)
 
 if (NOT EVHTP_DISABLE_EVTHR)
     list (APPEND LIBEVHTP_SOURCE_FILES  thread.c)