Change parameters for REST API endpoints (date related)

1. Combine from-block, to-block and start-date, end-date into two parameters like start and end. That parameter can take number or Date string as value. That way we'll reduce numbers of parameters and solve potential problems with priorities of ranges.

2. Include page-num page-size pagination on every endpoint with date ranges. Afterwards include the border value in the return.

@dan @mzander ^