Cannot append() number 0 to instance of Series

[BowTiedAztec]

Describe the bug
If you attempt to append() the value 0 to a Series, it fails with error:

Param Error: newValues cannot be null or undefined

Any other real value (positive or negative) seems to work fine.

To Reproduce

Simply try this:

new Series([1, 2, 3]).append(0, 3);

If you change the above to the following, it works fine:

new Series([1, 2, 3]).append(0.1, 3);

For now I am working around this by appending 0.0001 to my series, but it's obviously not ideal.