* show error when trying to create file or folder that already exists
* add test for file that already exists
* add folder tests
* fix error messages
* hide Properties folder
* update comment
* don't allow adding duplicate database references
* add test
* addressing comments
* remove XML checking from databaseReferenceExists()
* change to get
* add system database reference for VS
* a few fixes
* update tests
* update tests
* fix tests after merge
* addressing comment to make logic a little more clear
* fix replacing SSDT reference name in tree
* Adding reading SqlCmdVars from project file
* organized apiWrapper, added calls
* Adding test to confirm deployment/script gen profiles with sqlcmd vars
* convert system database references from SSDT
* remove empty ItemGroup if no other database references
* fix baseline files
* also update sqlproj if system database references were added in SSDT since the sqlproj got updated with ADS imports
* undo change
* move updating system db references out of updateProjectForRoundTrip()
* update test to have an already updated system db ref
* add clean target after merge from master
* add await
* addressing comments
* add database references to same itemgroup
* show database references in tree
* update tests
* refresh project tree after a reference is added
* addressing comments
* add validation
* Add test
* sort imports
* add dacpacs
* able to add reference to appropriate master dacpac
* able to add reference to a dacpac
* Add a few tests
* fix tests
* fix wording
* fix adding reference to same database
* add project tests
* fix test for windows
* addressing comments
* Adding another test
* update tests
* fix build error
* Test code for round tripping feature
* Fixed tests. Edited updateImportedTargetsToProjFile method to push newly added import target to the list.
* Added couple more tests
* Addressed comment
* Initial changes for Import database as new project
* Functionally complete code
* Initial changes for Import database as new project
* Functionally complete code
* Resolved conflicts with latest changes. Also did some code refactoring.
* Addressed comments. Added unit tests.
* Addressed comments
* Moved ExtractTarget enum from azdata to mssql
* Addressed comments
* Fixed indentation in project templates
