Process: drop commLen

It is only used on Linux to optimize memory handling in case the command
changes to a smaller-or-equal string.

This "optimization" however causes more code bloat and maintenance cost
on string handling issues than it gains.

Process.h

@@ -66,7 +66,6 @@ typedef struct Process_ {
    pid_t ppid;
    pid_t tgid;
    char* comm;  /* use Process_getCommand() for Command actually displayed */
-   int commLen;
    int indent;
 
    int basenameOffset;