… the Integrated IDE

A new dialog box was added that allows :
1. To choose the perspective that you want to use, when Integrated IDE starts.
2. To switch to other perspective while working with one.
The dialog can be improved by adding a 'Remember me' checkbox, to avoid asking to choose perspective again and again.

…pectives

…ted perspectives"

This reverts commit db8b04e. The approach failed.

…ted perspectives

This commit would save instance of project-manager of particular perspective. This would enable re-switching to a perspective after switching to the other perspective.

…ed perspectives