add "right to left" and alignments to "Default Text Styling" lab

[nitzan dori]

Hi,

a lot of my emails I write in hebrew but the default text style is
always set to left to right
so if I'm writing some line with Hebrew and English it gets all messed
up...

I saw that you made a lab to address such issues but I was
disappointed when I found out that only some basic styles are
editable....


tnx, Nitzan