1541 Send to interactive doesn't work when interactive is virtual env Adds support for project-specific interpreters to EnsureReplWindow and GetReplId. Updates callers to find and provide the project. Adds VirtualEnvironmentSendToInteractive test. Slight refactoring of ReplWindowTests.
1541 Send to interactive doesn't work when interactive is virtual env
Adds support for project-specific interpreters to EnsureReplWindow and GetReplId.
Updates callers to find and provide the project.
Adds VirtualEnvironmentSendToInteractive test.
Slight refactoring of ReplWindowTests.

enricosada/VisualStudio-SharedProject,mousetraps/xtvs-common,Microsoft/VisualStudio-SharedProject,mousetraps/xtvs-common