* Fix vulnerability check in tc7200_password_disclosure_v2

Use an encrypted zero block to identify the binary settings backup data.

* Make tc7200_password_disclosure_v2 compatible with new pycrypto

The decryption routine uses AES in ECB mode. The pycrypto module is used for this routine. ECB does not involve any initialization vector (IV). However routersploit uses one that is 16 NUL bytes. Older pycrypto versions just ignored this, but newer versions (at least since 2.6) error on using an IV with ECB.

* tc7200_password_disclosure_v2: adapt test to the binary check

* add missing import

* Adding travis

* Fixing .travis.yml

DIR-300 B1 with firmware 2.02 may have '\nuser' after admin password.

* Bump v3.0.0

* Adding Slack invitation link

Introduce `Exploit.validate_setup` method in order to check whether
Exploit's setup is correct. In most case scanarios we will check
if `Exploit.target` is not `None`. When exploit need custom
validation logic please overwrite `validate_setup`.

LGTM

CentOS installation instructions were not complete

Add juniper defaults

Added installation instructions of openSUSE Tumbleweed to the README file.

* Router detected as vulnerable while its not #305

* Fixed typo error

* Check status code instead of string

The HTTP HEAD method in general doesn't return the content of the body, unless it is a redirection page, so line `and len(response.text) > 500:` will never be true if second line of check `response = http_request(method="HEAD", url=url)` get a response.

As result, devices seem no vulnerable when actually it is.

Data:
```
HEAD /rom-0 HTTP/1.1
Host: 192.168.254.254
Connection: keep-alive
Accept-Encoding: gzip, deflate
Accept: */*
User-Agent: python-requests/2.18.4


HTTP/1.1 200 OK
Content-Type: application/octet-stream
Date: Sat, 01 Jan 2000 00:18:54 GMT
Last-Modified: Wed, 01 Jan 1930 00:18:54 GMT
Content-Length: 16384
Server: RomPager/4.07 UPnP/1.0
EXT:
```

My suggestion is just to check whether content type doesn't return "text/html" as value, so it correct this issue and keep the previous false positive fixed.

`and "html" not in response.headers['Content-Type']:`
or
`and response.headers['Content-Type'] == "application/octet-stream":

That'is it.

* Create multi_hedwig_cgi_exec.py

* update to proper format

* remove whitespace

* remove u

* Fixing payloads

* Pep fixes