Create Project class(es) to store session data

[DamianSuess]

As a user, I want to be able to select a single project file to perform my work. First, we need a class structure to load XML data.

Design and implement project output.

Acceptance Criteria

• Consider file extension ".liteproj" or something similar to ".sqlproj" to not clash with VS for now.
• Save object data
• Load object data into memory
• Output data compatible with Visual Studio's ".sqlproj" file format for future enhancement
  • See also: Database Project Settings

Out of Scope

• Loading data into Project window