* module/language/elisp/README: New file containing some notes.
* module/language/elisp/compile-tree-il.scm: New file with compilation code.
* module/language/elisp/spec.scm: Updated language definition.
* module/system/base/syntax.scm (keywords): Don't enable :keywords, it
breaks code that may assume that ':foo is a symbol, like boot-9.
* module/*.scm: Don't use :keywords, use #:keywords. The user can decide
if she wants #:keywords in their .guile, and :keywords might make us
compile modules differently.