Keep brackets around capture link annotation, to protect spaces
2019-07-27  Carsten Dominik  <carsten.dominik@gmail.com>
	* lisp/org-capture.el (org-capture-fill-template): Keep [[]]
	around the %l link annotation.
When capture is called from a buffer and the template includes a %l
annotation, then this link needs to be enclosed in [[ ... ]].  The
default link is a search link that searches for the line at point -
and when the link contains whitespace, it needs to be part of the link.