In numeric mode - treats digit '0' and decimal point '.' as numeric

[FriarTech]

I have been using sc-im for a while now with no issues. A couple of days ago I was typing up a column of numbers in numeric mode that I needed summed and noticed that things weren't quite what I expected.

The data was
.5
10
10
.5
.5
.5
.5

Which should be 22.5
But my totals in sc-im showed 45.

I realized I had assumed that decimal points would be treated as such in numeric mode.

So then I thought I'd enter every decimal with a leading 0

That also didnt work - as everytime I hit the '0' it would move the cursor to the leftmost column.

So I created two options --> numeric_zero and numeric_decimal. When these are each set, the corresponding zero and decimal will initiate numeric entry, but only when numeric mode is also set.

[andmarti1424]

Great job! I will test this and merge.
I do not use the numeric mode that is why did not find this bugs earlier.
Again, thanks for this patch.