Ensure that local variable upload_path is defined

[joncave]

Merge upload_payload and parse_upload_response so that the upload_path variable is defined for use in error messages in the event of failure.

If the WAR upload request fails the upload response parsing code bombs out due to an undefined variable. To reproduce start a fake Tomcat server:

$ mkdir -p /tmp/tomcat/manager
$ touch /tmp/tomcat/manager/html
$ cd /tmp/tomcat/ 
$ python -m SimpleHTTPServer
Serving HTTP on 0.0.0.0 port 8000 ...

Run the exploit:

msf > use exploit/multi/http/tomcat_mgr_upload  
msf exploit(tomcat_mgr_upload) > set RHOST 127.1.1.1
RHOST => 127.1.1.1
msf exploit(tomcat_mgr_upload) > set RPORT 8000
RPORT => 8000
msf exploit(tomcat_mgr_upload) > set FingerprintCheck false
FingerprintCheck => false
msf exploit(tomcat_mgr_upload) > exploit
[*] Started reverse handler on 127.0.0.1:4444 
[*] 127.1.1.1:8000 - Retrieving session ID and CSRF token...
[*] 127.1.1.1:8000 - Uploading and deploying oe1yNfhtJ3cdvYL0...
[-] Exploit failed: NameError undefined local variable or method `upload_path' for #<Msf::Modules::Mod6578706c...