Standardized the naming of functions which control the writing of fields etc.

to have the prefix 'write' rather than 'output'

So outputTime() -> writeTime()

but 'outputTime()' is still supported for backward-compatibility.

Also removed the redundant secondary-writing functionality from Time
which has been superseded by the 'writeRegisteredObject' functionObject.

tutorials/multiphase/potentialFreeSurfaceFoam/oscillatingBox/system/controlDict

@@ -57,7 +57,7 @@ functions
     {
         type            forces;
         functionObjectLibs ("libforces.so");
-        writeControl   outputTime;
+        writeControl   writeTime;
         patches         (floatingObject);
         pName           p;
         UName           U;