capture the target framework version as an app property. use the target framework version for projects.
Merge pull request #387 from Particular/issue-378-hotfix

Capture the user-supplied target framework instead of always using .net 4.0
close project designers when unfolding
Merge pull request #388 from Particular/issue-378-hotfix-workaround

Workaround for Nupattern/vs bug. Close project property windows when unfolding t4 templates. Fixes issue #378.
bump vsix version to 2.1.2
Merge branch 'hotfix-2.1.2'