Add 'make fix' command
Let pip use a local download cache
Add python2 to build matrix
travis already sets the TRAVIS environment variable
Sort Python versions
Updated introductory sentences to clarify purpose
Add a list of sample projects
clarify the TRAVIS conditional in the makefile
Revert "clarify the TRAVIS conditional in the makefile"

This reverts commit 702d082180925f46b5d298f0e245ae23ffd1eff9.
fix conflicts with master
Merge pull request #40 from jacebrowning/python2

Add python2 to build matrix
Add workspace cleaning to clean-all
Use PIP_CACHE_DIR variable
Merge pull request #39 from jacebrowning/pip-cache

Let pip use a local download cache
Not all of the samples are "libraries"
Add instruction to set the default Python version
Switch example to Doorstop
Expand instructions with a source code link
Merge branch 'master' into pep8radius
Remove 'shell' syntax from code blocks

Pygments doesn’t understand this and GitHub doesn’t quite render it
correctly.