Loads a grid from a folder. Path to the folder and grid id (considered to be grid's filename) is required.
After a grid is loaded, an attempt to find all it's related models in the very same folder is made.
All models must be found in order to successfully import a grid. Grid's version must be the same as the version of
H2O it is imported into.
version - API version
gridImportV3 - Import arguments
Key to the imported Grid. Grid's key is the same as serialized in the binary file given.
java.io.IOException - Error reading grid or related models.