Initial lesson about python string formatting using the format() method
Removed solutions
Clarified the note about field widths and added an example
Clarified the sentence about the print command output
Fixed typos
Changed line width to 80 characters for the poem formatting and added an explanation
Added machine-readable vs human-readable output, and updated the challenges
Added a lesson on making packages in R.
Updates based on suggestions by jdblischak
Updates based on suggestions by jdblischak
Merge branch 'master' of https://github.com/jainsley/bc
Fixed typo
Small edits to lesson on creating R packages.
switching flag order for jekyll
Added novice reference page on recognising shell, Python and editors within a shell window and how to exit from these
1.  Modifying home page validator to make sure that the contact address *isn't* 'admin@software-carpentry.org'.
2.  Adding tests for validator's checking of helpers list.
Making instructions for checking bootcamp home pages more prominent
Improve "Recognising prompts" section

- Add images
- "How to exit" right after the images.
Fix English at Prompt reference

Thanks to @mikej888.
Merge pull request #1 from jdblischak/package

Small edits to lesson on R package development