Carry over the order of magnitude in ranges

[marcolagi]

For example,

Before the Hubble Telescope scientists predicted an age of the universe ranging from 10 to 20 billion years

should be parsed as:

[Quantity(1e+10, "year"), Quantity(2e+10, "year")]

instead of

[Quantity(10, "year"), Quantity(2e+10, "year")]