fix(engine): make historic statistics query precise

related to CAM-1659, CAM-1579
fix(cockpit/page reload): prevent page reloading when unnecessary

This commit prevents a page reload/refresh when for example select an activity from the tabs below the diagram.
Also prevent losing the tab scope and fix the "Asignee" typo.

Closes CAM-1727
docs(cockpit/templates): add template starting and ending comments

It helps to find in which template you might have to make change when you use the browser developer tools.
Those comments are striped out when building for production with grunt.
fix(cockpit/build): remove old reference to jquery-ui from bower.json

Because having a hash with the same key twice in it is not valid JSON.
chore(tomcat): Upgrade tomcat version, use maven central tomcat

- Upgraded tomcat version to 7.0.35
- Use tomcat distribution fom maven central
test(engine-integration): add testcase for PA embedded process engine plugin

- works on all app servers except JBoss, because of different implementation inside
JBoss subsystem

related to CAM-1778
feat(engine/history): unify activity instance query mapping

related to #CAM-1656
fix(engine/receive): sequential test case with user task

related to #CAM-1612
fix(engine): update execution id in database after parallel async execution

closes #CAM-428
feat(engine): extend TaskQuery

Extended the TaskQuery API by following functionality:
* processDefinitionNameLike()
* processInstanceBusinessKeyLike()
* taskAssigneeLike()
* processVariableValueLike()
* processVariableValueGreaterThan()
* processVariableValueGreaterThanOrEquals()
* processVariableValueLessThan()
* processVariableValueLessThanOrEquals()
* taskVariableValueLike()
* taskVariableValueGreaterThan()
* taskVariableValueGreaterThanOrEquals()
* taskVariableValueLessThan()
* taslVarrableValueLessThanOrEquals()

related to CAM-1724
fix(engine): execute executionListeners of boundaryEvents

related to CAM-1788