Merge pull request #23 from migueldvb/local

Add a paragraph about simulation data and reference to Turk et al 2011.
Abbreviate figure for consistency with other occurrences in the paper
Typo-level changes
Delete trailing whitespace
Mention Paper II (NDF)
Sentence on HDX
Use non-breaking space in Figure references
Signpost sub-sections for Section 2 per Norman's comment.
Address software is not plural noun.
change coordinate -> deliberate
clarify validation means semantic as well as syntactic
Try to improve wording in para 3 of section 2.1.2
refine argument about TEMP ambiguity in 2.1.2
add Norman's EXPTIME example refinement
add tweak about English forces limit on audience of file
Add remarks about HDX and NDX models
Tweak address for Norman to approved form
Remove EXPTIME paragraph in 2.1.2.

Its overkill/duplicates arguments made for TEMP
Rewrite of the last 3 para (or so) of 2.1.2

Try to simplify examples, unify the argument and generally clean
up the wording.
Replace utilize with use