added files for testing lesson
Split 08 SQL notebook into two sections

The current notebook combined adding and dropping tables and changing
the data in existing tables into one long section. These are logically
separate sets of commands and grouping them together created a bit of a
wall of text.
Add Update to SQL lesson on creating and modifying databases

When showing students how to add and remove records it will be natural for
them to ask how to modify an existing record. This demonstrates how to do
this using Update in a few lines.
Removed 'next steps'
commented NaN lines in test
fixes after reviewe for 04-cond.md
Minor fixes to 03-func and 04-cond
Add updated markdown version of 08 SQL notebook
corrected the missing wild card
times for shell, python, git, sql
only keep n,median; remove mean,min,max
Rough slides, missing phd comics image
Good enough git slides to share?
Uploaded lesson on reading and writing .csv, including exploration of arguments in the functions
Updates to lesson and associated files
Merge branch 'master' of https://github.com/swcarpentry/bc into matlab-05-defensive

Conflicts:
	novice/matlab/02-loop.md
	novice/matlab/03-func.md
	novice/matlab/04-cond.md
fixed duplicate output
adding md file
Change file extension from rmd -> Rmd.
Set eval=FALSE for code chunk with hypothetical setwd statement.

Also change some of the output in md file because of system differences,
e.g. the number of decimal places to display.