Land rapid7#2580 - Don't try to create war without exe

Author: wchen-r7

msfpayload

@@ -215,7 +215,7 @@ if (cmd =~ /^(p|y|r|d|c|h|j|x|b|v|w|n)$/)
     exe  = Msf::Util::EXE.to_executable($framework, arch, plat, buf)
     if(!exe and plat.index(Msf::Module::Platform::Java))
       exe = payload.generate_war.pack
-    else
+    elsif exe
       exe  = Msf::Util::EXE.to_jsp_war(exe)
     end