Fix required properties with zero value errors.

'required' properties that have a zero value
generate an error when they should not. This is
due to if (source[property]) check in getProperty,
instead of (source[property] !== undefined)
Merge pull request #52 from bjnortier/required-property-with-zero-value-generates-error

Fix required properties with zero value errors.
Add a new file ‘.jshintignore’
Remove unnecessary links from the documentation
Add a new file ‘Hintfile’
Fix ‘TypeError: Object [object Object] has no method 'addError'’
Merge branch 'master' of github.com:Baggz/Amanda
Fix ‘TypeError: Object [object Object] has no method 'addError'’
Fix ‘Amanda 0.4.3 breaks validation of 'falsey' values’
Release 0.4.4
Merge pull request #54 from Baggz/dev

Amanda v0.4.4
Remove ‘throw new Error’, release 0.4.5
Merge pull request #55 from Baggz/v0.4.5

Remove ‘throw new Error’, release 0.4.5
update from upstream