Onscreen IDE & dynamic instant update [_v0.5.4_]

MINOR UPDATES :
[X] since 1.5.3, DirectScrolledFrame uses ScissorAttrib (DisplayRegion) (which can’t be overriden at descendant level) instead of clip planes, so the linemarks were clipped. It’s fixed by parenting them directly to the DSF instead of the canvas, and scrolled separately as the canvas scrolls.
[X] fixed inefficient shader reload
[X] smart paste : the pasted multiple lines now auto-indented following the 1st line
[X] added repeated character(s) insertion

[EDIT] (repeated characters interface) :
[+] simplified, no longer using “insert” buttons. Replaced by pressing ENTER/RETURN at the “Counts” or “Fill until column” textbox.
[+] the textboxes values are preserved