Added the "More to know" section to the adapter documentation.
Documented Dropbox adapter. Closes #3.
Documented Ftp adapter. Closes #4.
Documented the local adapter. Closes #5.
Documented Rackspace adapter. Closes #6.
Documented SFTP adapter. Closes #7.
Documented ZipArchive adapter. Closes #9.
Documented WebDav adapter. Closes #8.