Beginning in July, the city will flip the switch on a new website that will put huge chunks of municipal data online for public inspection. The system is the first in use by a New England city based on a cloud-computing model, the ethereal moniker for systems that allow anyone with an Internet connection to plug into a much larger database without storing the information locally. In use from Seattle to New York City, the OpenData software by Washington-based Socrata Inc. has the potential to swing open the floodgates on the last decade's worth of work by Somerville technologists, demographers, and planners, who have spent millions of dollars and thousands of hours quantifying and analyzing the city's problems. “Somerville has continually been at the forefront of innovative government management and transparency, and we're excited to roll out this latest data tracking tool to bring real-time information to residents," said Mayor Joseph A. Curtatone in a prepared statement. Chief among the information to become available will be real-time data on 311 calls for service, mirroring a system in place in Boston that allows residents to watch a complaint or request move through the ranks of government until it is addressed.