define contradiction and move negation, close #230
uniformize footnotes
index
inhabited
wording
basepoints
index
move a couple solutions to the solutions file
index
index
index and 'formally', close #229
typo
Some letter B
Merge branch 'master' of github.com:HoTT/book

Conflicts:
	equivalences.tex
	hits.tex
	homotopy.tex
	preliminaries.tex
	reals.tex
Index letters Z and Y. But ...

why doesn't "ZF" and "Zermelo--Fraenkel set theory" appear in the index?!
index letters u v w x y
add expanation of beta/eta to products section #233
add expanation of beta/eta to products section #233
index letter t
Merge branch 'master' of github.com:HoTT/book