Changed the form/Basic Test

We defined an div as owner of the basic form. As ExtJS suggested in its doc we
now take a panel as an owner. Tests passes now for 4 and 5.
Fixed selection/FeatureModel test

Replaced the testing-method for selecting a row, because onRowMouseDown() is
no longer available in ExtJS5. The new method should be equivalent.
Merge pull request #323 from KaiVolland/form-basic-test-extjs5

Changed the form/Basic Test
Merge pull request #324 from KaiVolland/selection-featuremodel-extjs5

Fixed selection/FeatureModel test
Merge branch 'extjs5' of https://github.com/geoext/geoext2 into extjs5