fix shields.io badge download

[justinmk]

https://bugs.launchpad.net/ubuntu/+source/openssl/+bug/861137

neovim/neovim#3308 (comment)

badges/shields#439 (comment)

To test this, there isn't much we can do except commit it. The wget invocations works fine on my local ubuntu VM, so there's some difference between the version of ubuntu that travis is running.

[justinmk]

That didn't work, different issue now:

--2015-09-12 22:11:03--  https://img.shields.io/badge/clang_analysis-0-00ff00.svg
Resolving img.shields.io (img.shields.io)... 104.18.45.160, 104.18.44.160
Connecting to img.shields.io (img.shields.io)|104.18.45.160|:443... connected.
OpenSSL: error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure
Unable to establish SSL connection.

Trying --secure-protocol=TLSv1 now.

[justinmk]

That also failed.

--2015-09-12 22:26:00--  https://img.shields.io/badge/clint-0-green.svg
Resolving img.shields.io (img.shields.io)... 104.18.45.160, 104.18.44.160
Connecting to img.shields.io (img.shields.io)|104.18.45.160|:443... connected.
OpenSSL: error:14094438:SSL routines:SSL3_READ_BYTES:tlsv1 alert internal error
Unable to establish SSL connection.

Falling back to http://.