fix a couple typos
Merge pull request #280 from jasonkriss/typos

fix a couple minor typos
Unify way of calling include_attribute? in attibutes and association methods.
Merge pull request #282 from morgoth/unify-calling-include_attribute

Unify way of calling include_attribute? in attibutes and association methods
Change gem.homepage to new location
Merge pull request #285 from bquorning/patch-1

Change gem.homepage to new location
fix travis links

The existing links work, but redirect.
Merge pull request #289 from teeparham/patch-2

fix travis links