- New functions `foreign-regexp/case-fold-available-p', `foreign-regexp/ext-regexp-available-p'
  and `foreign-regexp/case-fold-available-p'.

- When a foreign regexp does not support some search option,
  set empty string to each search option indicator string.

- Raise error on switching search options when it's not supported by
  current foreign regexp.

- Update menu items for each search options properly
  when they are not supported.
- New replacement option `Eval Replacement'.
- Improved messages from commands that toggles search options.
- Updated replacement script of perl and ruby
  for a replacement option `Eval Replacement'.
- Make commands `bin/foreign-regexp-replace-aux.*' to begin search from current position.
- Make commands `bin/foreign-regexp-replace-aux.*' region aware.
- Fix bugs in commands `bin/foreign-regexp-replace-aux.*' with zero width match.
- New option `limit' for `bin/foreign-regexp-replace-aux.*'.
- New fucntion `foreign-regexp/.format-external-command-arg'.
- New option `limit' for function `foreign-regexp/replace/search-by-external-command'.
- Changed data format of the return value from external replace command.
- Rename eval-rpla to eval-replacement.
- Add document for search option `foreign-regexp/toggle-eval-replacement'.
-- Merge branch 'master' of github.com:k-talo/foreign-regexp.el

   Conflicts:
             foreign-regexp.el