bug #41167: fixes for various Parfait errors

https://savannah.gnu.org/bugs/?41167

Hello,
I made fixes for various Parfait static code analysis errors, such as memleaks and file descriptor leaks.
Hope it helps.

applied with a bit of modification
Adds screen.exe to src/.gitignore
add caption on top as option

nice patch from Neal Fultz, slightly adapted
draw hardstatus using default colors

when using caption splitonly, it would leak standout colors to background