Create a folder named after the artifactId

[brunoborges]

Currently, when VS Code generates a project, it simply drops the files in the selected folder. Ideally, a new folder (with the same name as artifactId) should be created in the selected folder.

[Matthew-Dong]

Also prefer auto-creating a folder after generating the project to make the directory clean. When downloading from start.spring.io, the folder name aligns with the Artifact id.

@Eskibear please take a look if we can make this change targeting next release.

[Eskibear]

When downloading from start.spring.io, the folder name aligns with the Artifact id.

I remember previously the files are located in root folder of the downloaded .zip pack. But just now I had a check, finding there's an extra param baseDir in the target URL now. I'll update it.

[Eskibear]

fixed in #75