Move varnish triggers from user tales to CDB_TableMetadata

Closes #197
Jira ref CDB-241
html for new starting page done
Merge branch 'master' into feature/CDB-777
actions for new welcome page
actions for new welcome page
adding specs file
Allows to add and remove colors in the legend
Removes comment
save info window state for each schema

When a query is applied and the info window fields
are changed according to the query they may be reset 
if the user changes the query (to do a temporal analysis 
query for example).

This code saves sue state so when the user come back 
to the desired query infowindow fields are restored.
CDB-1147 #resolve - fixed problem with infowindow custom template
Merge branch 'feature/centralize-varnish-trigger' of git://github.com/strk/cartodb into release/2.5.6
Disable pg_notify on _CDB_TableMetadata_Updated

See https://github.com/CartoDB/cartodb/pull/241
Merge branch 'master' into feature/CDB-777
Remove call to Table#add_python
Remove call to Table#add_python
Update NEWS.md
CDB-777 #resolve - added new videos for empty dashboard tables
Merge remote-tracking branch 'origin/feature/CDB-777' into release/2.5.5
added https to vimeo embeded videos
Merge remote-tracking branch 'origin/feature/CDB-777' into release/2.5.5