Make Lorem Ipsum text easier to find and edit
Modify hero_unit.html and index.html to include references to the
following partials in _includes/custom :
    /welcome.html
    /grid_item_left.html
    /grid_item_middle.html
    /grid_item_right.html
Make the home page text easier to find and edit by placing the
content in the same folder.
Name the partials according to their position on the home page
so that they are easy to identify.
Include a description on how to modify the text in README.md