Currently if the user selects a folder while importing a project, the "open project" dialog will show a list of all the (projectfile, project managers) pair that can be used.
For example, if we select a directory with t1.pro and t2.pro, we get two entries for qmake, one for t1.pro and the other for t2.pro, along with the entry for "Generic Project Manager", etc.

However, all the selections are equivalent, as OpenProjectDialog::selectedUrl always returns the folder name, and not the selected .pro file. This patch attempts to fix this issue.