Improve asset detection

[AtiDev17]

Explained in issue: #24

TDLR: Before this PR the tool only imported folders that are defined in a list. Now it imports any folder if either the manifest file exists or if one of the target folders exist. If none of them exists the user need to manually import the asset.

target_folders = [
    "aniBlocks", "data", "Environments", "Light Presets", "People",
    "Props", "ReadMe's", "Render Presets", "Render Settings", "Runtime",
    "Scenes", "Scripts", "Shader Presets", "Cameras", "Documentation"
]