Better output for certs with a lot of subject alt names

[csstaub]

Improve output for certs with a lot of subject alt names.

For example, this is what google.com's current cert shows (note the many SANs):

$ ./certigo dump certs/google.com.pem
Enable Date: 2016-05-25 15:03:23 +0000 UTC
Expiry Date: 2016-08-17 14:42:00 +0000 UTC
Algorithm Type: SHA256-RSA
Subject Info:
    CommonName: *.google.com
    Organization: [Google Inc]
    OrganizationalUnit: []
    Country: [US]
    Locality: [Mountain View]
Issuer Info:
    CommonName: Google Internet Authority G2
    Organization: [Google Inc]
    OrganizationalUnit: []
    Country: [US]
    Locality: []
Subject Key ID  : 7C:D4:C5:48:38:F5:22:2C:4B:20:AA:B1:BD:A1:08:CA:B6:4B:6E:3C
Authority Key ID: 4A:DD:06:16:1B:BC:F6:68:B5:76:F5:81:B6:BB:62:1A:BA:5A:81:2F
Alternate DNS Names: [*.google.com *.android.com *.appengine.google.com *.cloud.google.com *.google-analytics.com *.google.ca *.google.cl *.google.co.in *.google.co.jp *.google.co.uk *.google.com.ar *.google.com.au *.google.com.br *.google.com.co *.google.com.mx *.google.com.tr *.google.com.vn *.google.de *.google.es *.google.fr *.google.hu *.google.it *.google.nl *.google.pl *.google.pt *.googleadapis.com *.googleapis.cn *.googlecommerce.com *.googlevideo.com *.gstatic.cn *.gstatic.com *.gvt1.com *.gvt2.com *.metric.gstatic.com *.urchin.com *.url.google.com *.youtube-nocookie.com *.youtube.com *.youtubeeducation.com *.ytimg.com android.clients.google.com android.com g.co goo.gl google-analytics.com google.com googlecommerce.com urchin.com www.goo.gl youtu.be youtube.com youtubeeducation.com]
Serial Number: 9101476628582717928