exercises on plump ordinals
refer to Taylor's book, clarify injectivity of i_Ord
fix typos in 6.12.1, close #656
errata for d5b2a65
tone down comment about strong normalization, close #649
fix exercises on colimits, close #655
add index entries
errata for f78d42e
Merge branch 'master' into snorm

Conflicts:
	formal.tex
Merge branch 'master' into lemma6.12.1

Conflicts:
	errata.tex
Merge branch 'master' into colimits

Conflicts:
	errata.tex
Merge branch 'master' into plump

Conflicts:
	reals.tex
	references.bib
oops, didn't complete merge
Merge pull request #667 from mikeshulman/snorm

tone down comment about strong normalization, close #649
Merge pull request #657 from mikeshulman/lemma6.12.1

fix typos in 6.12.1, close #656
Merge pull request #671 from mikeshulman/colimits

fix exercises on colimits, close #655
Merge pull request #637 from mikeshulman/plump

exercises on plump ordinals
Mark Errata (auto)