api end point to retrieve list of connections
Modernize the model tests

Added initialize_sql

Made small changes

Made some small changes
Merge pull request #477 from sammyshj/modernizemodeltests

Modernize the model tests
Merge pull request #478 from pradyu1993/PR472

api end point to retrieve list of connections
Update api and corresponding models
Added username and requested_by
Added tests
Fixed make lint errors
Added BmarkMgr