Installation in editable mode fails when collection is not specified under namespace/collection directory

[priyamsahoo]

While installing the collection in editable mode, the code looks for the collection files under the namespace/collection directory to copy them to the build folder.

This might not always be true, as users can also put collection files in other directories. When this happens, the CLI tool fails to install them in editable mode.

[cidrblock]

Fixed by #144