Add Alternative to inject Add_this service into template
Merge branch 'master' into add_this
continuation on add_this
Merge branch 'master' into add_this
ensure the default code for the ADD_THIS_DATA setting is the same as the previous add_this code from template
Merge branch 'master' into add_this
substitute add_this by social_buttons_code
Merge pull request #573 from areski/add_this

Add Alternative to inject Add_this service into template
AddThis support now replaceable through new SOCIAL_BUTTONS_CODE option
no need to add social_buttons_code to global_context
really deprecate ADD_THIS_BUTTONS
updated changelog
initial doc, needs fleshing out
revert default behaviour of social buttons
added sharenice setup explanation
new social_buttons doc describing share_nice and socialshareprivacy integration
finished socialshareprivacy setup, sort of
merged master