(#21) Throw error if recovery_message contains '

Previously, if you declared an `osx::recovery_message` resource that
contained an apostrophe/single-quote ('), the exec used to set the
recovery message would fail (because the exec references the message
within single quotes).

This commit will call the fail() function if a recovery_message contains
an apostrophe and alert the user to the failure.  The spec was also updated
and worked for me in 1.8.7 and 1.9.3
Appease puppet-lint's quoting errors

This commit single-quotes lines that don't contain variables and escapes
out any quotes that might be in those lines.
Use two-space tabs
Config option to enable/disable 'natural' scrolling
Merge pull request #17 from yuhunglin/disable-natural-scrolling

disable 'natural' scrolling
Show hidden files
Add osx::finder::show_hidden_files to README
Merge pull request #23 from glarizza/bug/recovery_message_alert

(#21) Throw error if recovery_message contains '
Use boxen::osx_defaults instead of property_list_key

property_list_key depends on RubyCocoa to work and RubyCocoa doesn't
work on Ruby 2.0
Merge pull request #34 from boxen/mavericks-fix

Fix recovery_message on Mavericks
Add osx setting for Dock position
Fix dock position
Add spec for dock position
Add setting to pin dock at the 'start', 'end', or 'middle'
Update README with dock position and pin_position
Merge pull request #35 from billyvg/master

Add settings to set the dock's screen edge position as well as pinning position
Fix Readme
Fix Readme
Merge remote-tracking branch 'upstream/master' into show-hidden-files

Conflicts:
	README.md
Fix README.md