Move procExeBasenameOffset to main Process structure

This drops procExeLen, as that field is implicit by strlen(Process->procExe)

Process.h

@@ -111,6 +111,9 @@ typedef struct Process_ {
    /* The main process executable */
    char *procExe;
 
+   /* Offset in procExe of the process basename */
+   int procExeBasenameOffset;
+
    /* Tells if the executable has been replaced in the filesystem since start */
    bool procExeDeleted;