Add doc for "-p" option.

README.md

@@ -21,6 +21,7 @@ optional arguments:
   -H [HOSTS [HOSTS ...]], --host [HOSTS [HOSTS ...]]
                         Hosts as input separated by space
   -j, --json            Enable JSON in the output
+  -p, --pretty          Print pretty and more human readable Json
   -h, --help            Show this help message and exit
 ```
 
@@ -30,6 +31,8 @@ Port is optional here. The script will use 443 if not specified.
 
 `-j, --json`	Use this if you want to only have the result in JSON
 
+`-p, --pretty` Use this with `-j` to print indented and human readable json
+
 `-H, --host`	Enter the hosts separated by space
 
 `-h, --help` Shows the help and exit
@@ -58,4 +61,4 @@ Example only with the `-j` argument which show the JSON only. Perfect for piping
 ```bash
 narbeh@narbeh-xps:~/ssl-checker$ ./ssl_checker.py -j -H test.com narbeh.org:443 
 {'test.com': {'valid_till': '2020-01-24', 'valid_from': '2017-01-15', 'cert_alg': u'sha256WithRSAEncryption', 'cert_ver': 2, 'cert_sn': 73932709062103623902948514363737041075L, 'cert_exp': False, 'issuer_c': u'US', 'issuer_cn': u'Network Solutions DV Server CA 2', 'issuer_o': u'Network Solutions L.L.C.', 'validity_days': 1104, 'issuer_ou': None}, 'narbeh.org': {'valid_till': '2018-05-18', 'valid_from': '2018-02-17', 'cert_alg': u'sha256WithRSAEncryption', 'cert_ver': 2, 'cert_sn': 319510066429286596971677345373584681421772L, 'cert_exp': False, 'issuer_c': u'US', 'issuer_cn': u"Let's Encrypt Authority X3", 'issuer_o': u"Let's Encrypt", 'validity_days': 90, 'issuer_ou': None}}
-```
+```