#1592 Caret invisible after SCI_SETCARETPERIOD

[Nils Nordman]

There's a problem when toggling the caret blink period using SCI_SETCARETPERIOD. Specifically, setting the period to 0 leaves the caret invisible, if it was invisible at the time of the call. Moving the cursor causes the caret to be redrawn again. This is on Gtk+3 in case it matters.

[Neil Hodgson]

Fix committed as [48c7ed].

[Nils Nordman]

That was fast, thanks Neil!