Issue title: Review color accessibility
 Issue body: It seems some of our colors are not passing AA WCAG. Please double check.
https://sap.github.io/fundamental/colors.html



 Comments: 
 Comment 0: @xak
Have you more details? Manu could chime in.
Some color combinations of the whole color pallete will not pass but those combinations should not be in use, as far as I know.

The text color/background color combination used should be mostly this ones.
<img width="1305" alt="screen shot 2018-02-27 at 10 14 05" src="https://user-images.githubusercontent.com/22662903/36720008-fa93caf0-1ba6-11e8-8fc1-74d37c9f7d87.png">

@LeoT7508 
Let's wait to get some more details on this from Manu, 
 Comment 1: @joseegm 

I'll look into this when I get into the office. 
 Comment 2: Neither action color passes. I did not test them all.

![screen shot 2018-02-27 at 8 51 37 am](https://user-images.githubusercontent.com/424119/36735336-8d7aa08e-1b9b-11e8-8ad6-aae369f50422.png)

![screen shot 2018-02-27 at 8 54 19 am](https://user-images.githubusercontent.com/424119/36735451-dfaa5174-1b9b-11e8-950c-f222fb58d3c7.png)
 Comment 3: Buffffff. At this point in the conversation last year i though we were all safe
https://github.com/SAP/techne/issues/757#issuecomment-310975617

 Comment 4: I was just noticing on the cloud commerce invision screens, their colors are a bit darker blues and lighter grays. https://projects.invisionapp.com/share/Q3FEPPRD57V#/screens/274270862
 Comment 5: The Teal on white we are using on the documentation site is also failing. 

<img width="721" alt="site-color-fail" src="https://user-images.githubusercontent.com/15215400/36736833-25358b8e-1b9f-11e8-821d-8c848defe118.png">

 Comment 6: @joseegm 

This was all addressed in the email I sent out, I will close the issue. 
 Comment 7: This is still not finished
 Comment 8: @joseegm 

This is finished. 
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