fix *ON-LEFT-RECURSION* in example-left-recursion.lisp

When implementing Nikodemus' suggestion, the variable
ESRAP:*ERROR-ON-LEFT-RECURSION* had to be renamed to
ESRAP:*ON-LEFT-RECURSION*. The instances in
example-left-recursion.lisp have been forgotten.

* Rename ESRAP:*ERROR-ON-LEFT-RECURSION* -> ESRAP:*ON-LEFT-RECURSION*

* Rename TEST-{LAMBDA -> RA}
fix typo in COMPILE-NONTERMINAL

The produced named lambda should be called COMPILED-NONTERMINAL
instead of COMPILE-NONTERMINAL
added syntax (function FUNCTION-NAME) for function terminals

* FUNCTION-NAME is called to consume some input and return a
  production

* The system version has been bumped from 0.11 to 0.12 and a feature
  :ESRAP.FUNCTION-TERMINALS is pushed onto *FEATURES* when the system
  is loaded

* New example in example-function-terminals.lisp

* Added unit tests FUNCTION-TERMINALS.{PARSE-INTEGER, PARSE-A} and
  EXAMPLE-FUNCTION-TERMINALS.{INDENTED-BLOCK,READ}

* Extended README and doc/esrap.texinfo

Based on Nikodemus' and Kilian's ideas and feedback.
update homepage, author, maintainer information

* Change "Homepage & Documentation" link in README, esrap.lisp:
  http://{nikodemus -> scymtym}.github.com/esrap/

* Add :author "Nikodemus Siivola <nikodemus@random-state.net>"
      :maintainer "Jan Moringen <jmoringe@techfak.uni-bielefeld.de>"
  in esrap.asd

* Change repository and project page links in doc/esrap.texinfo
  github.com/{nikodemus -> scymtym}