Python Project Properties - Update: Configuration: Virtual Environment

[ebresie]

As of v0.3.0, when open project properties, many of the field do not populate correctly and have placeholder logics. This issue is to resolve this. This is broken down into each category to focus the work to smaller chunks

Python Project Properties: Configuration: Virtual Environment - Depending on how VEnv get implemented, this may allow VEnv to be populated and used instead of a specified platform. If VEnv get included in platforms, then this may go away. This would be a list of available virtual platform (i.e., not python platforms) which if VEng is enable would be used for the project in place of the above platform. Need to evaluate if breaking this up makes more sense or keeping them together simplifies things. There may be overlap with other items such as the interface with virtual environment

This may overlap some with Platform update ticket #32 and the Virtual Environment interface ticket #22

This updates further relative to the initial project properties added as part of #20 updates.