Fix special characters in pause and message menu
Fix game pause in singleplayer
Use fixed-width format specifiers in serializeStructToString
Revert "Use fixed-width format specifiers in serializeStructToString"

This reverts commit 875f1327a47f78d783c3abc7f7acc3977dc286ec.
Fixed width format specifiers are only officially availale in C99 and C++11.