fix WSJ to new default URL, some minor tweaks
add DOIs to ERIC
Delete dataMode "block" and "line"

 * These values are no longer needed (and are therefore somehow deprecated).
 * Deleted all occurrencies of block or line as dataMode
Merge pull request #828 from zuphilip/data-mode

Delete dataMode "block" and "line"
[Flickr] Don't attempt to download photos if downloading is disabled
(disabled by the author in Flickr that is)
[RIS] Account for possible \u2028 \u2029 characters
[RIS} Actually detect \u2029.
See 891ea29335a52f2c12c6f0f431a6063c88908f06
Thanks @zuphilip
Merge branch 'master' of https://github.com/zotero/translators