Remove unused function params
try using SQL
Set maximum number of items retrived by API to 100
Update docs with max value of limit API argument
Import missing libs for SQL request

bind as slave also in session.
Merge branch 'sql-marvin' into issue-query-perf-improvements
use app.id instead of app_id for tasks. app_id could be null
Use cached value for number of project tasks
Added project_tasks method to cached apps
Tests for new cache function
Use cached tasks in tasks/browse
Updated default theme
Merge branch 'issue-query-perf-improvements' of https://github.com/PyBossa/pybossa into issue-query-perf-improvements

* 'issue-query-perf-improvements' of https://github.com/PyBossa/pybossa:
  use app.id instead of app_id for tasks. app_id could be null
Removed print
Update default theme
Function in cache to retrieve number of taskruns for given task
Tests for n_task_taskruns function
Remove with_context decorators
do task_run also with SQL
Merge branch 'issue-query-perf-improvements' of https://github.com/PyBossa/pybossa into issue-query-perf-improvements