[#1257] Fixed meta og:description elements
[#1257] Fixed meta og:description elements

On project updates pages the ulrize filter was converting URIs to actual
html elements in the meta og:description elements.

Fixed by removing the urlize filter & also limit chars to 500. There is
no hard limit on that field but Google told that Facebook only shows max
300 so this gives us additional space if needed.

akvo/akvo-rsr,akvo/akvo-rsr,akvo/akvo-rsr,akvo/akvo-rsr