Vendor psutils and remove neko

plugins/system/ps/host/host_freebsd_amd64.go

@@ -0,0 +1,28 @@
+// +build freebsd
+// +build amd64
+// Created by cgo -godefs - DO NOT EDIT
+// cgo -godefs host/types_freebsd.go
+
+package host
+
+const (
+	sizeofPtr      = 0x8
+	sizeofShort    = 0x2
+	sizeofInt      = 0x4
+	sizeofLong     = 0x8
+	sizeofLongLong = 0x8
+)
+
+type (
+	_C_short     int16
+	_C_int       int32
+	_C_long      int64
+	_C_long_long int64
+)
+
+type Utmp struct {
+	Line [8]int8
+	Name [16]int8
+	Host [16]int8
+	Time int32
+}