postgres stuff

[oxarbitrage]

the search api call use postgres database to get the markets with volume so we don't display all the possible crosses but only the ones that had volume in the last 24 hours.

this database postgres is populated by a script in another project: https://github.com/oxarbitrage/bitshares-python-api-backend/blob/master/postgres/import_markets.py the file runs once a day br cron and get the active market pairs.

udf search call use data from this populated database, may not be suitable for the UI, can need another way.