Used update stamp instead of dirty flag for SVM models

- Compared with the modification date of the model file
- Updated db structure, marked all models as dirty initially
- Adjusted tests
Fixed time mocking issue

- CMTest_TH::timeInit() should reset the mock time to the system time
Moved SVM training to a new cli command "maintenance start-local"
Synchronized "shared" maintenance jobs
Merge branch 'master' of github.com:cargomedia/CM into issue-1201

Conflicts:
	resources/db/update/26.php
Merge pull request #1201 from fauvel/issue-1201

Make SVM model files local