Fixes # 61

The make_twitter_request function no longer throws an error when trying
to access data in a response from a protected account.

Also, get_friends_followers_ids now respects a parameter values of 0 for
friends/followers.
Fixing indentation error in Example 17

Caused the function to end prematurely since a return statement was
indented one level too far
Fixed errors in Example 21 - Harvesting a user's tweets
Fixed minor error in Example 21 - Harvesting a user's tweets
Adding more flexiblity to Example 21 and guarding against possible Exception
Adding optimization to Example 21 - Harvesting a user's tweets
Update README.md
Fixing long code lines for copyedit
Merge branch 'master' of https://github.com/ptwobrussell/Mining-the-Social-Web-2nd-Edition
Adding experimental support for AWS-based VMs

Refactored the Vagrantfile to support AWS configuration
information, checked in two additional recipes that are needed for
AWS-based VMs, and fixed a a glitch in the mtsw2e recipe related to
str.each being phased out of Ruby 1.9 (which the AWS-based image uses
whereas the Virtualbox based image is still using 1.8)

The AWS-backed configuration does seem to work, although the Vagrant
plugin needs to mature a bit (e.g. support port forwarding and sync'd
folders better) before most people will want to use it. We'll also want
to add a password to the IPython configuration file to protect notebooks
that are hosted as well...
Minor tweaks to Chapter 1 code readability
Adding more robustness to make_twitter_request recipe
Minor tweaks for Chapter 2 for added clarity
Fixed a long code line and an edge case in opening a file
Fixing a couple of long code lines
Fixing long code line
Several minor fixes...

* Fixed long code lines
* Renamed get_user_info => get_user_profile
* Retooled a recipe to be framed in terms of extracting tweet entities
  from arbitrary text as opposed to a profile, now that Twitter extracts
  entities from profile descriptions
Updating example titles to be consistent with copyedited text version
Fixing a few more example title inconsistencies
Applying copyedit fixes to code comments