Add option to relocate translate window to bottom (top?).

[yupm]

For monitors in portrait mode, the image is squeezed between two sidebars. I think being able to change the placement of the translate window would be good for user experience. Not sure how hard it is but I am willing to give a try.

[blueaxis]

I am willing to give a try

Feel free to do so. I think its would be better if there is an option to place it on top/bottom/right.

Also, please see this guide for commit messages, so I don't end up squashing the merge like last time. I don't strictly follow the reference sheet, but I'd enforce one rule: use imperative, present tense verb as the first word of the message. Thanks!

[yupm]

I am sorry I wanted to do it this week, but fell sick from food poisoning. Probably from the onsen egg combini bento. JLPT exams on July 2nd so I will be free to focus on this only from July 3rd..