Use proper naming for position/location

[wooorm]

Currently, location and position is used interchangeably, while they differ.
This confusion derives from node.position, which holds a location, and a location has start and end set to a position.

I propose:

• position for node.position (aka “location”, “positional info”)
• point for node.position.start, node.position.end (as it refers to a point in a file)

[anko]

To clarify: you propose changes only to terminology, not to the functional spec?

[wooorm]

Yes, only terms! Something like this:

 ### `Node`
 
 ...

 ```idl
 interface Node {
   type: string;
   data: Data?;
-  position: Location?;
+  position: Position?;
 }
 ```
 
 ...
 
-#### `Location`
+#### `Position`
 
-**Location** references a range consisting of two points in a [Unist
+**Position** references a range consisting of two points in a [Unist
-file][file].  **Location** consists of a `start` and `end` position.
+file][file].  **Position** consists of a `start` and `end` point.
 And, if relevant, an `indent` property.
 
 ...
 
 ```idl
-interface Location {
+interface Position {
-  start: Position;
+  start: Point;
-  end: Position;
+  end: Point;
   indent: [uint32 >= 1]?;
 }
 ```
 
-#### `Position`
+#### `Point`
 
-**Position** references a point consisting of two indices in a
+**Point** references a point consisting of two indices in a
 [Unist file][file]: `line` and `column`, set to 1-based integers.  An
 `offset` (0-based) may be used.
 
 ```idl
-interface Position {
+interface Point {
   line: uint32 >= 1;
   column: uint32 >= 1;
   offset: uint32 >= 0?;
 }
 ```

What do you think?

[anko]

I like it. 👍 The naming confused me when I first read the readme, and this would help.