Remove remaining traces of Chicken CG

INSTALL.md

@@ -62,16 +62,6 @@ Mac OS X users will want to build from source.
 **Note**: If you install ChezScheme from source files, building it locally, make sure
 you run `./configure --threads` to build multithreading support in.
 
-### Chicken
-
-Chicken Scheme offers binary distributions (and source tar balls) from
-
-+ https://code.call-cc.org/
-
-You can find chicken in many package managers.
-
-After installing chicken scheme you may need to install the 'numbers' package.
-
 ### Racket
 
 Racket is available from:

Notes/Directives.md

@@ -112,7 +112,7 @@ Syntax:
 The given instructions are passed directly to the code generator, to be
 interpreted in a backend-specific way.
 
-Currently known backends are: `chez`, `chicken`, `racket` and `gambit`.
+Currently known backends are: `chez`, `racket` and `gambit`.
 
 ## Backend Specific Directives
 
@@ -139,9 +139,3 @@ corresponding file-loading code:
 Note the file is loaded referencing an absolute path of the first
 matching file found, except when it's the current directory in which
 case the file is simply referenced as `./library_name`
-
-### Chicken
-
-The directive should be scheme code which is inserted directly into the generated
-code. This can be used, for example, to import external libraries, e.g.
-`%cg chicken (use posix)`.

README.md

@@ -58,8 +58,8 @@ Summary of new features:
 + Better type checker implementation which minimises the need for compile
   time evaluation.
 + New Chez Scheme based back end which both compiles and runs faster than the
-  default Idris 1 back end. (Also, optionally, Chicken Scheme, Racket and Gambit
-  can be used as targets).
+  default Idris 1 back end. (Also, optionally, Racket and Gambit can be used
+  as targets).
 + Everything works faster :).
 
 A significant change in the implementation is that there is an intermediate