Landing page copy and content update

[stevenabadie]

https://docs.google.com/document/d/1nHsf1PqzqLOCdAS7OY7cTqHjwOD7jPJ_le5JGPSGec4/edit?usp=sharing

[stevenabadie]

@tfischbach I dumped all of the current copy on the codeforfoco.org homepage into that google doc. Figured it would be good to get it out of the design to better understand what we're currently saying.