Tune memory manager page

This PR fixes the memory manager page by:

- removing links to non-existent sections;
- fixing links with bad anchors;
- fixing incorrect language tag for code snippets

Author: tengqm

content/en/docs/tasks/administer-cluster/memory-manager.md

@@ -63,13 +63,11 @@ Important topic in the context of Memory Manager operation is the management of
 
 ## Memory Manager configuration
 
-Other Managers should be first pre-configured (section [Pre-configuration](#pre-configuration)). Next, the Memory Manger feature should be enabled (section [Enable the Memory Manager feature](#enable-the-memory-manager-feature)) and be run with `Static` policy (section [Static policy](#static-policy)). Optionally, some amount of memory can be reserved for system or kubelet processes to increase node stability (section [Reserved memory flag](#reserved-memory-flag)).
+Other Managers should be first pre-configured. Next, the Memory Manger feature should be enabled and be run with `Static` policy (section [Static policy](#policy-static)). Optionally, some amount of memory can be reserved for system or kubelet processes to increase node stability (section [Reserved memory flag](#reserved-memory-flag)).
 
 ### Policies 
 
-Memory Manager supports two policies. You can select a policy via a `kubelet` flag `--memory-manager-policy`.
-
-Two policies can be selected:
+Memory Manager supports two policies. You can select a policy via a `kubelet` flag `--memory-manager-policy`:
 
 * `None` (default)
 * `Static`
@@ -93,7 +91,6 @@ The [Node Allocatable](/docs/tasks/administer-cluster/reserve-compute-resources/
 
 The Kubernetes scheduler incorporates "allocatable" to optimise pod scheduling process. The foregoing flags include `--kube-reserved`, `--system-reserved` and `--eviction-threshold`. The sum of their values will account for the total amount of reserved memory.
 
-
 A new `--reserved-memory` flag was added to Memory Manager to allow for this total reserved memory to be split (by a node administrator) and accordingly reserved across many NUMA nodes. 
 
 The flag specifies a comma-separated list of memory reservations per NUMA node.
@@ -150,7 +147,7 @@ The default hard eviction threshold is 100MiB, and **not** zero. Remember to inc
 
 Here is an example of a correct configuration:
 
-```shell
+```none
 --feature-gates=MemoryManager=true 
 --kube-reserved=cpu=4,memory=4Gi 
 --system-reserved=cpu=1,memory=1Gi 
@@ -225,14 +222,19 @@ This error typically occurs in the following situations:
 * the pod's request is rejected due to particular Topology Manager policy constraints 
 
 The error appears in the status of a pod:
+
 ```shell
-# kubectl get pods
+kubectl get pods
+```
+
+```none
 NAME         READY   STATUS                  RESTARTS   AGE
 guaranteed   0/1     TopologyAffinityError   0          113s
 ```
 
 Use `kubectl describe pod <id>` or `kubectl get events` to obtain detailed error message:
-```shell
+
+```none
 Warning  TopologyAffinityError  10m   kubelet, dell8  Resources cannot be allocated with Topology locality
 ```
 
@@ -253,6 +255,7 @@ Also, search the logs for occurrences associated with the Memory Manager, e.g. t
 ### Examine the memory manager state on a node
 
 Let us first deploy a sample `Guaranteed` pod whose specification is as follows:
+
 ```yaml
 apiVersion: v1
 kind: Pod
@@ -274,6 +277,7 @@ spec:
 ``` 
 
 Next, let us log into the node where it was deployed and examine the state file in `/var/lib/kubelet/memory_manager_state`:
+
 ```json
 {
    "policyName":"Static",