Merge remote-tracking branch 'origin/topic/seth/rdp'

* origin/topic/seth/rdp: (31 commits)
  Improved transition into SSL/TLS from RDP.
  Fixes tests in RDP branch.
  add a special case to the X509 code that deals with RDP certificates.
  A few more changes to handling encryption in RDP.
  Adds some comments and fixes a broxygen warning.
  Fixes another optional part of an RDP unit.
  Support RDP negotiation requests optionally and support zero length cookies.
  Changed UTF-16 to UTF-8 conversion to be more lenient.
  Fixed an issue with parse failure on an optional field.
  Removing a stray printf from RDP analyzer.
  Another big RDP update.
  New script to add a field to rdp.log when the connection is upgraded to SSL.
  Huge updates to the RDP analyzer from Josh Liburdi.
  FreeRDP test trace showing SSL encryption -- RDP analyzer does not currently handle this and SSL analyzer does not identify it either
  Wireshark test trace for native encryption -- generates a binpac error
  Delete RDP-004.pcap
  Delete nla_win7_win2k8r2.pcap
  Update dpd.sig
  Fixed typo
  Added check for connection existence
  ...

BIT-1340 #merged

testing/btest/scripts/base/protocols/rdp/rdp-proprietary-encryption.bro

@@ -0,0 +1,4 @@
+# @TEST-EXEC: bro -r $TRACES/rdp/rdp-proprietary-encryption.pcap %INPUT
+# @TEST-EXEC: btest-diff rdp.log
+
+@load base/protocols/rdp

testing/btest/scripts/base/protocols/rdp/rdp-to-ssl.bro

@@ -0,0 +1,5 @@
+# @TEST-EXEC: bro -r $TRACES/rdp/rdp-to-ssl.pcap %INPUT
+# @TEST-EXEC: btest-diff rdp.log
+# @TEST-EXEC: btest-diff ssl.log
+
+@load base/protocols/rdp

testing/btest/scripts/base/protocols/rdp/rdp-x509.bro

@@ -0,0 +1,5 @@
+# @TEST-EXEC: bro -r $TRACES/rdp/rdp-x509.pcap %INPUT
+# @TEST-EXEC: btest-diff rdp.log
+# @TEST-EXEC: btest-diff x509.log
+
+@load base/protocols/rdp