DOC: Move all docs into en/ subdirectory (#1505)

* DOC: Move all docs into en/ subdirectory

PR #1502 is working on adding a Chinese translation to the docs. In
general, I encouraged this (in #1452) as a path towards getting useful
translated content in the game without requiring a massive
refactor/rearchitecting of everything.

To support this, this takes the first step of moving our docs into an
en/ subdirectory, so that other languages can live alongside. No effort
is made at this time to support or select between alternate languages;
this is a pure-rename refactor.

src/Documentation/doc/en/basic/terminal.md

@@ -0,0 +1,102 @@
+# Terminal
+
+The Terminal is a console emulator program that lets you interface with other [Servers](servers.md) in the game.
+It can be accessed by clicking the `Terminal` tab on the navigation menu on the left-hand side of the game (you may need to expand the 'Hacking' header in order to see the `Terminal` tab).
+Alternatively, the shortcut Alt + t can be used to open the Terminal.
+
+## Filesystem (Directories)
+
+The Terminal contains a very basic filesystem to help you organize files into different directories.
+Note that this is **not** a _true_ filesystem implementation and instead relies almost entirely on string manipulation.
+For this reason, some features found in real-world filesystems do not exist in our Terminal. For example:
+
+- Tab autocompletion does not work with relative paths
+- **`mv` and `rm` commands only accept full filepaths in their arguments.**
+  **They do not act on directories.**
+
+These features are typically in Linux filesystems and have not yet been added to the game.
+
+## Directories
+
+In order to create a directory, simply name a file using a full absolute Linux-style path:
+
+    /scripts/myScript.js
+
+This will automatically create a "directory" called `scripts`.
+This will also work for subdirectories:
+
+    /scripts/hacking/helpers/myHelperScripts.js
+
+Files in the root directory do not need to begin with a forward slash:
+
+    thisIsAFileInTheRootDirectory.txt
+
+Note that **there is no way to manually create or remove directories.**
+Creation and deletion of "directories" is automatically handled as you create, rename, or delete files in game.
+
+## Absolute vs Relative Paths
+
+Many Terminal commands accept both absolute and relative paths for specifying a file.
+
+An absolute path specifies the location of the file from the root directory (/).
+Any path that begins with the forward slash is an absolute path:
+
+    $ nano /scripts/myScript.js
+    $ cat /serverList.txt
+
+A relative path specifies the location of the file relative to the current working directory.
+Any path that does **not** begin with a forward slash is a relative path.
+Note that the Linux-style dot symbols will work for relative paths:
+
+    . (a single dot) - represents the current directory
+    .. (two dots) - represents the parent directory
+
+    $ cd ..
+    $ nano ../scripts/myScript.js
+    $ nano ../../helper.js
+
+For additional details about specifying paths and references in scripts, see [Scripts](scripts.md).
+
+## Argument Parsing
+
+When evaluating a terminal command, arguments are initially parsed based on whitespace (usually spaces).
+Each whitespace character signifies the end of an argument, and potentially the start of new one.
+For most terminal commands, this is all you need to know.
+
+When running scripts, however, it may be important to know specific detail, especially two main points:
+
+- Quotation marks can be used to wrap a single argument and force it to be parsed as a string.
+  Any whitespace inside the quotation marks will not cause a new argument to be parsed.
+- Anything that can represent a number is automatically cast to a number, unless it's surrounded by quotation marks.
+
+Here's an example to show how these rules work.
+Consider the following script `argType.js`:
+
+    export async function main(ns) {
+        ns.tprint("Number of args: " + ns.args.length);
+        for (var i = 0; i < ns.args.length; ++i) {
+            ns.tprint(typeof ns.args[i]);
+        }
+    }
+
+Then if we run the following terminal command:
+
+    $ run argType.js 123 1e3 "5" "this is a single argument"
+
+We'll see the following in the Terminal:
+
+    Running script with 1 thread(s), pid 1 and args: [123, 1000, "5", "this is a single argument"].
+    argType.js: Number of args: 4
+    argType.js: number
+    argType.js: number
+    argType.js: string
+    argType.js: string
+
+## Chaining Commands
+
+You can run multiple Terminal commands at once by separating each command
+with a semicolon (;). For example:
+
+    $ run foo.js; tail foo.js
+
+Chained commands do **not** wait for functions like `hack` or `wget` to finish executing, and so may not always work as expected.