Dynamically cache LVGL

[kisvegabor]

Is your feature request related to a problem? Please describe.
Now we support only a single LVGL version which is packed into the project creator.

Describe the solution you'd like
No LVGL should be hardcoded in the Project creator, Instead the requested LVGL version should be dynamically downloaded and saveed . These LVGL version act as a cache, so next time they shouldn't be downloaded.

As the user can select only minor version we don't have to worry about having too many LVGL version cached.

When a new patch version is released (E.g. v9.2.3 -> v9.2.4) the saved v9.2 version should be overwritten.

Describe alternatives you've considered
None.

Additional context
See #21