Rethink the load_version and load_with_datetime interfaces

[MrPowers]

Description

There are currently a few different interfaces for time traveling:

Option 1:

DeltaTable("some_path", version=1)

Option 2:

dt = DeltaTable("some_path")
dt.load_version(1)

Option 3:

dt = DeltaTable("some_path")
dt.load_with_datetime("2018-01-26T18:30:09Z")

We should consider providing a single interface:

dt = DeltaTable("some_path").time_travel(version=1)
dt = DeltaTable("some_path").time_travel(version_as_of="2018-01-26T18:30:09Z")

I don't think methods like these should be limited to only taking string arguments: load_with_datetime(datetime_string: str)

Users should be able to pass in Python date and datetime objects as well.

[ion-elgreco]

Good one, we can perhaps consolidate the load_version and load_with_datetime into a single function:

DeltaTable.load_to(version: int | datetime)