org-protocol: Pass optional value using query in url to capture from protocol.
* lisp/org-protocol.el: (org-protocol-convert-query-to-plist): New
function.
(org-protocol-do-capture): Use new function.
(org-protocol-data-separator): Change default separator.
When org-protocol's url has query, org-capture get query using
plist-get from store-link. For example:
Url is "org-protocol:/capture:/URL/TITLE/BODY?key=value"
org-capture can get (:key value) with (plist-get org-store-link-plist :query).
TINYCHANGE