Force text mode for >=grep-2.22 (bug #574480).

--- a/Build/PrepMonoDev.sh
+++ b/Build/PrepMonoDev.sh
@@ -3,7 +3,7 @@
 
 sed 's!<SignAssembly>true</SignAssembly>!<SignAssembly>false</SignAssembly>!g' ../KeePass/KeePass.csproj > ../KeePass/KeePass.csproj.new
 sed 's! ToolsVersion="3.5"!!g' ../KeePass/KeePass.csproj.new > ../KeePass/KeePass.csproj.new2
-cat ../KeePass/KeePass.csproj.new2 | grep -v 'sgen\.exe' > ../KeePass/KeePass.csproj
+cat ../KeePass/KeePass.csproj.new2 | grep -va 'sgen\.exe' > ../KeePass/KeePass.csproj
 rm -f ../KeePass/KeePass.csproj.new2
 rm -f ../KeePass/KeePass.csproj.new