[Lazarus] Source Editor enhancement mini-patch

[Hans-Peter Diettrich]

Giuliano Colla schrieb:

> However there's a Delphi IDE small feature which I miss when using 
> Lazarus: a quick mouse access to the Jump Back/Jump Forward function, to 
> navigate history. I find keyboard shortcuts (CTRL-H and Shift-CTRL-H) 
> more cumbersome.

Just a note: Delphi shorcuts for these are Alt-Left and Alt-Right.

I also would like to have clickable forward/back items. They also might 
become part of the editor gutter?

DoDi