More documentation fixes

README.md

@@ -164,7 +164,7 @@ you can install this tool via
 The command-line arguments consist mostly of mapping and/or drawing files.
 The files and other arguments are processed *in order*, so for example a
 drawing can use all mapping files specified *before* it on the command line.
-In the same symbol is defined by multiple mapping files, later mappings take
+If the same symbol is defined by multiple mapping files, later mappings take
 precedence (overwriting previous mappings).
 
 Here is the output of `svgtiler --help`:
@@ -198,7 +198,9 @@ SYMBOL specifiers:
 
   'filename.svg':   load SVG from specifies file
   '<svg>...</svg>': raw SVG
-  (context) -> ...: function computing SVG
+  -> ...@key...:    function computing SVG, with `this` bound to Context with
+                    `key` set to symbol name, `i` and `j` set to coordinates,
+                    and supporting `neighbor` and `includes` methods.
 ```
 
 ## About

package.json

@@ -1,7 +1,7 @@
 {
   "name": "svgtiler",
   "description": "Tool for drawing diagrams on a grid, combining grids of SVGs into a big SVG figure",
-  "version": "1.0.10",
+  "version": "1.0.11",
   "repository": {
     "type": "git",
     "url": "git+https://github.com/edemaine/svg-tiler.git"

src/svgtiler.coffee

@@ -429,6 +429,7 @@ extension_map =
 help = ->
   console.log """
 Usage: #{process.argv[1]} (...options and filenames...)
+Documentation: https://github.com/edemaine/svgtiler#svg-tiler
 
 Optional arguments:
   --help                Show this help message and exit.
@@ -454,7 +455,9 @@ SYMBOL specifiers:
 
   'filename.svg':   load SVG from specifies file
   '<svg>...</svg>': raw SVG
-  -> ...:           function computing SVG, with context available as this/@
+  -> ...@key...:    function computing SVG, with `this` bound to Context with
+                    `key` set to symbol name, `i` and `j` set to coordinates,
+                    and supporting `neighbor` and `includes` methods.
 """
   #object with one or more attributes
   process.exit()