feat: add npm query cmd

Implemented Arborist `querySelectorAll` method that enables easier
retrieval of installed packages using a css-selector-like syntax.

It also includes a new command `npm query` that exposes that same logic
to users of the npm cli.

Ref: npm/rfcs#564

docs/content/commands/npm-query.md

@@ -0,0 +1,125 @@
+---
+title: npm-query
+section: 1
+description: Dependency selector query
+---
+
+### Synopsis
+
+<!-- AUTOGENERATED USAGE DESCRIPTIONS START -->
+<!-- automatically generated, do not edit manually -->
+<!-- see lib/commands/query.js -->
+
+```bash
+npm query <value>
+```
+
+<!-- automatically generated, do not edit manually -->
+<!-- see lib/commands/query.js -->
+
+<!-- AUTOGENERATED USAGE DESCRIPTIONS END -->
+
+### Description
+
+The `npm query` command allows for usage of css selectors in order to retrieve
+an array of dependency objects.
+
+### Piping npm query to other commands
+
+```bash
+# find all dependencies with postinstall scripts & uninstall them
+npm query ":attr(scripts, [postinstall])" | jq 'map(.name)|join("\n")' -r | xargs -I {} npm uninstall {}
+
+# find all git dependencies & explain who requires them
+npm query ":type(git)" | jq 'map(.name)' | xargs -I {} npm why {}
+```
+
+### Configuration
+
+<!-- AUTOGENERATED CONFIG DESCRIPTIONS START -->
+<!-- automatically generated, do not edit manually -->
+<!-- see lib/utils/config/definitions.js -->
+#### `global`
+
+* Default: false
+* Type: Boolean
+
+Operates in "global" mode, so that packages are installed into the `prefix`
+folder instead of the current working directory. See
+[folders](/configuring-npm/folders) for more on the differences in behavior.
+
+* packages are installed into the `{prefix}/lib/node_modules` folder, instead
+  of the current working directory.
+* bin files are linked to `{prefix}/bin`
+* man pages are linked to `{prefix}/share/man`
+
+<!-- automatically generated, do not edit manually -->
+<!-- see lib/utils/config/definitions.js -->
+
+#### `workspace`
+
+* Default:
+* Type: String (can be set multiple times)
+
+Enable running a command in the context of the configured workspaces of the
+current project while filtering by running only the workspaces defined by
+this configuration option.
+
+Valid values for the `workspace` config are either:
+
+* Workspace names
+* Path to a workspace directory
+* Path to a parent workspace directory (will result in selecting all
+  workspaces within that folder)
+
+When set for the `npm init` command, this may be set to the folder of a
+workspace which does not yet exist, to create the folder and set it up as a
+brand new workspace within the project.
+
+This value is not exported to the environment for child processes.
+
+<!-- automatically generated, do not edit manually -->
+<!-- see lib/utils/config/definitions.js -->
+
+#### `workspaces`
+
+* Default: null
+* Type: null or Boolean
+
+Set to true to run the command in the context of **all** configured
+workspaces.
+
+Explicitly setting this to false will cause commands like `install` to
+ignore workspaces altogether. When not set explicitly:
+
+- Commands that operate on the `node_modules` tree (install, update, etc.)
+will link workspaces into the `node_modules` folder. - Commands that do
+other things (test, exec, publish, etc.) will operate on the root project,
+_unless_ one or more workspaces are specified in the `workspace` config.
+
+This value is not exported to the environment for child processes.
+
+<!-- automatically generated, do not edit manually -->
+<!-- see lib/utils/config/definitions.js -->
+
+#### `include-workspace-root`
+
+* Default: false
+* Type: Boolean
+
+Include the workspace root when workspaces are enabled for a command.
+
+When false, specifying individual workspaces via the `workspace` config, or
+all workspaces via the `workspaces` flag, will cause npm to operate only on
+the specified workspaces, and not on the root project.
+
+This value is not exported to the environment for child processes.
+
+<!-- automatically generated, do not edit manually -->
+<!-- see lib/utils/config/definitions.js -->
+
+<!-- AUTOGENERATED CONFIG DESCRIPTIONS END -->
+## See Also
+
+* [dependency selector](/using-npm/dependency-selector)
+