Centralized setting of chunk options for novice R materials.
Added back fig.path option to novice R lesson 01.
Make jekyll ignore Rmd files.
Added Makefile for converting R Markdown files to Markdown.
Added rmarkdown to list of .PHONY targets.
Fixed a couple of typos. (references to another dataset)
Fixed another typo
Fix goostats error when using options -J 100 -r

goostats was returning an error with the options -J 100 -r in lesson 5.
-J was being passed to head which returned invalid option. To fix this
I add option handeling with getopts.
Merge pull request #631 from swcarpentry/typo-fix

Fixed a couple of typos. (references to another dataset)
Remove newline
Changed rmarkdown to rmd.
Changed one last instance of rmarkdown to rmd.
Merge pull request #633 from jensv/fix-shell-05-script-goostats

Fix shell 05-script goostats option error
Improvements to the Introduction and Simple Patterns sections of intermediate/regex.

Main changes:
- Fixed the links to other sections and the Glossary.
- Added files containing the 'evil' data to data/evil.
- Created some exercises for the Simple Patterns section.
- Corrected a few typos and made some paragraphs clearer.
- Split up the Simple Patterns section into subsections.
- Added the intermediate/regex section to the Makefile.
- Added an index page.
Merge pull request #569 from ctjacobs/creating-lesson-on-regular-expressions

Improvements to intermediate/regex
Merge pull request #626 from jdblischak/display_w_hooks

Makefile for converting R Markdown files to Markdown
Update 01-general.md
Merge pull request #637 from lsblakk/master

Two additions to the guide
Create new lesson 02 on forking

Create an empty lesson on forking and bump the other lesson numbers up accordingly.
add new extra lesson about forking

Add the first draft of a new lesson about forking. The lesson covers creating a fork, creating pull requests, and reasons for using a fork instead of working off of one repo. Leaves out the details of code review.

This encompasses most of the material that is in lesson 03. The plan is to rewrite 03 to focus on pull requests and code review. It should cover using pull requests from different branches in the same repo as well as between forks.