Fix spelling of coexistence (#120)

Author: godalming123

README.md

@@ -45,7 +45,7 @@ You need the following software:
 * Windows: Visual Studio 2013|2015 Community Edition (Windows) or higher
 
 ## Qt5 and Qt6 Notes
-We support both Qt5 and Qt6 builds but we don't support coesisteance of the DOtherSide library 
+We support both Qt5 and Qt6 builds but we don't support coexistence of the DOtherSide library 
 compiled in both ways. In other words the DOtherSide so name is the same compiled with Qt5 or Qt6.
 This is a current limitation but we could change this in future.