* Add small changes to README.md
* Add clarifications to CONTRIBUTING.md
* Split 'Locations and Formats'
* Rewrite 'Formats' paragraph
* Remove superfluous newline
* Remove superfluous <br />s
* Make the word 'Makefile' stand out
* Fix Markdown mark-up
Merge pull request #543 from stevenkoenig/readme-and-contributing-changes

Readme and contributing changes
Added novice reference page on recognising shell, Python and editors within a shell window and how to exit from these
Merge pull request #551 from mikej888/prompts

Added novice reference page on prompts and exits
Merged upstream changes since first repo clone
Merge pull request #2 from rbeagrie/swc-gh-pages

Merging upstream changes from Software Carpentry