Make getApplicationAccessToken public

For posting apprequests, we need to use the application access token
not the user one. It is easy to specify this in the parameters to api
call except that the method to retrieve it is protected. I can see no
obvious reason why.
Marked deprecated methods with @deprecated.
Constructor reuses $state local variable pulled from persistent storage.
fix curl ssl cacert invalid file
Add phpunit as a composer dependency, and ignore vendored files
Only require phpunit in development environment
Added the extra param: appsecret_proof to the oauth api calls
Removed duplicate multiline comment start
Merge pull request #69 from anankan/master

Added the proof of appsecret param to API calls
added relative link to the example
added color to the snippets
added composer usage example
Merge pull request #8 from dmnc/master

Make getApplicationAccessToken public
Merge pull request #10 from dharkness/deprecations

Add replacement method to @deprecated tags
Check isset before unset
Merge pull request #98 from stevenwoodson/master

Small fix to base_facebook.php
Merge pull request #61 from gary-rafferty/master

Add phpunit as a dependency in composer.json
Merge pull request #95 from facebook/gFosco.unset1

Check isset before unset
Merge pull request #96 from liuggio/master

3 huge issues solved.
Merge pull request #46 from dosercz/master

Fixed curl ssl invalid cert file
ETag support