Converted tabs to spaces in {src,test}/*.lisp, cl-hooks.asd

* {src,test}/*.lisp: converted tabs to spaces, updated copyright
* cl-hooks.asd: likewise
* README: likewise
Smarter restarts in run-hook in src/hook.lisp

* src/util.lisp (run-handler-with-restarts): removed; kind-of replaced
  by `signal-with-hook-and-handler-restarts'
  (with-hook-restarts): likewise
  (signal-with-hook-and-handler-restarts): new function; establish
  restarts to retry, skip handlers or hook or use values for either
* src/hook.lisp (run-hook :around t): removed; now done in next method
  (run-hook t): only establish hook, handler restarts if a handler
  actually signals an error; use `signal-with-hook-and-handler-restarts'
Faster common case run-hook in src/hook.lisp

* src/hook.lisp (run-hook t): if the combination is `progn', perform it
  inline
Use serial dependencies in cl-hooks.asd

* cl-hooks.asd (system cl-hooks): use serial dependencies
  (system cl-hooks-test): likewise
Bumped version 0.2.0 -> 0.2.1 in cl-hooks.asd

* cl-hooks.asd (system cl-hooks): bumped version 0.2.0 -> 0.2.1
  (system cl-hooks-test): likewise