Add link to gcloud-java from landing page

[ajkannan]

gcloud-java needs to be added to the Node.js landing page language-switcher menu (in the top left corner). Here's the associated logo:

[callmehiphop]

Currently all the logos within the language switcher are flat white svgs. I think we're going to want the gcloud-java logo to fit those same specifications.

[ajkannan]

That's a valid point. I chose that logo because I didn't find any white svgs icons for duke on https://duke.kenai.com/ (they all have the red nose and none were svgs). The duke icon was chosen in googleapis/google-cloud-java#127, and my rudimentary attempt to convert it into an svg didn't turn out well. Any thoughts @jgeewax?

[callmehiphop]

Decided to take a crack at it! Thoughts?

[ajkannan]

I like them, especially the one on the left since the icon will be small.

[jgeewax]

+1

[ajkannan]

Do you mind attaching a 24x24 svg of the left one so I can update the other landing pages? Thanks for making it!

[stephenplusplus]

Nice work, Dave!

[callmehiphop]

@ajkannan doesn't look like Github allows you to attach SVGs :<

Here's a link to the source code instead!
https://raw.githubusercontent.com/callmehiphop/gcloud-node/duke/docs/site/img/icon-lang-java.svg

Let me know if that works and stuff