Retrieve table row count from statistics rather than table scan

See https://wiki.postgresql.org/wiki/Slow_Counting
Use query parameters rather than Sprintf
Move statements out of Client

This reverts e071532d350c332e48d1fbe8a6a81712e789f574
Merge pull request #67 from cbandy/query-parameters

Build queries using parameters
Propertly initialize string slice for Tables() method
Implement client.fetchRows to reduce duplication
Set profiler sleep time to 30 seconds
Changelog
Add changelog dates
Detect 127.0.0.1 in js as local connection
Move table content into the API
Initial schema support

- List tables and views based on the current search path
- Use regclass to generate properly quoted table identifiers based on
  the search path
- Trust that the incoming table name is quoted properly