Path Header in KV Section Confusing Due to Merge of Forward-Slash Containing Section Name and KV Path

### Overview of the Issue

The Key / Value section of the Consul UI has a header that merges together the name of the section of the UI with the path of the key/value. The name section of the section having a forward slash in it "Key / Values" makes it look like it's parth of the key/value path, which is super confusing.

Further, the section name changes from "Key / Value" at the root of the KV tree to "Key / Values" (plural) when shown in the header when moving down the KV tree. Also super confusing.

### Reproduction Steps

### Describe the solution you'd like

1. Remove the confusing pluralization and name the section either "Key / Value" consistently, or, better yet, just name it "kv" so that it /does/ match the actual API path to the key-value pairs.
2. Fix the path header so that it isn't merging the UI section and the path to the nested key-value pairs. I'm agnostic on how to do this, but it should be clear what is a section of the UI and what is a kv path.

### Consul Version

All. Still exists as of 2.0.1

### Browser and Operating system details

All

### Screengrabs / Web Inspector logs

Start by reproducing the issue at the Consul UI KV page using the nested path shown in the issue, then trace the UI code that renders the path header and section label. Done means the section name is consistent and the UI clearly separates it from the nested key/value path.

Written by the indexing model from the issue text.