Editor user experience improvements

[pedrovelho]

While working on PrEstoCloud I had several annoying moments using the studio editor. I created this issue so we can improve this hopefully in a near future.

• Need to close the editor to save, this is really the most annoying one. I have often to close what I am doing just to save it because if I click outside the editor window it will close the current script without saving my changes. I suggest a save button that does not close the editor. Close button then close without saving, but why having this button if just clicking outside boils down to the same?

• When you open the editor window you cannot use the pg-up and down or arrows because focus is not set automatically. I suggest set focus inside automatically.

• Scrolling, so you must use the mouse wheel to scroll. If your file is a bit long you might click and drag the vertical scroll bar, but attention if you release the mouse button outside the window you accidentally loose all your work because the editor window close without saving. I propose we ask for saving before leaving or just ignore mouse release as a mouse click.

• The state of scrolling is not saved, each time document is open it starts from the beginning so we need to find ourselves again on the code. It would be much better if it opens already focusing on the last line.

[amouhoub]

@pedrovelho @fviale is this issue fixed including all of the aforementioned items ? if not can you please update this issue with a listing of still items. thank you in advance