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
Minor changes to the text based on feedback from users
fixes after reviewe for 04-cond.md
Added author contact details so I can collect usage stats
Minor fixes to 03-func and 04-cond
Add updated markdown version of 08 SQL notebook
Added additional challenge to 04-cond to combine conditional, per discussion with @jdblischak
replaced parameter with argument, identified argument with a defualt value of TRUE, and changed name of argument to use_boxplot
corrected the missing wild card
Updated new challenge wording to drop boolean and instead refer to the use_boxplot argument
Merge pull request #779 from jhollist/master

Added additional challenge to novice R lesson 04-cond to combine conditional statements.
updated index.md
Merge branch 'matlab-04-cond'
changed double to single quotes in 01-intro
changed single to double quotes in 02-reuse
rename "Miscellaneous" header