zshenv: Add alias for cams

Use mpv to show a cameras feed on the screen.

.zshenv

@@ -41,7 +41,7 @@ alias gwc='git ls-files | xargs cat | wc'
 alias c2pdf='enscript -r -2 --highlight=c --line-numbers -o - $(git ls-files | grep -v .png | grep -v .xcf | grep -v .map) | ps2pdf -'
 alias feh='feh -FZ'
 alias white='i3lock'
-alias cal='ncal -bM'
+alias cam='mpv --profile=low-latency --untimed /dev/video0'
 
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