English review

Review all texts in the whole site.
I think some of them need to be changed.

I would suggest to focus the revision on the main site sections as for example: 
- About - http://amkn.org/about/
- Disclaimer - http://amkn.org/about/disclaimer/
- Credits - http://amkn.org/about/credits/
- Research sites - http://amkn.org/ccafs-sites/
- Projects - http://amkn.org/ccafs-activities/
- etc.
