#1318 SVN r12909 introduced Linux crash due to missing file due to typo

[Andrew Cottrell]

The wxsitemeditor.cpp change for the "quickpropsclose32.png" to "quickpropsclose2.png" change on line 535 causes a crash on Linux as the quickpropsclose2.png file does not exist.

Line 535 needs to change back to quickpropsclose32.png.

Now to build and test to see if there are any other issues.

[Miguel Gimenez]

Fixed in [r12920], thank you.