Kernel+SystemMonitor: Add fault counters

This patch adds three separate per-process fault counters:

- Inode faults

    An inode fault happens when we've memory-mapped a file from disk
    and we end up having to load 1 page (4KB) of the file into memory.

- Zero faults

    Memory returned by mmap() is lazily zeroed out. Every time we have
    to zero out 1 page, we count a zero fault.

- CoW faults

    VM objects can be shared by multiple mappings that make their own
    unique copy iff they want to modify it. The typical reason here is
    memory shared between a parent and child process.

Applications/SystemMonitor/ProcessModel.h

@@ -21,6 +21,9 @@ public:
         Virtual,
         Physical,
         Syscalls,
+        InodeFaults,
+        ZeroFaults,
+        CowFaults,
         __Count
     };
 
@@ -49,6 +52,9 @@ private:
         size_t amount_virtual;
         size_t amount_resident;
         unsigned syscall_count;
+        unsigned inode_faults;
+        unsigned zero_faults;
+        unsigned cow_faults;
         float cpu_percent;
         int icon_id;
     };