* helm.el (helm--set-local-variable): New.
* helm.el (helm--let-internal, helm--let-variables): Renamed from helm-let-internal and helm--let-variables.
* helm.el (helm--set-local-variable): Allow binding after init.
* helm.el (helm--local-variables): new.
(helm-set-local-variable): use it.
(helm-create-helm-buffer): append helm--local-variables to helm--let-variables.
* helm-files.el (helm-ff-query-replace-in-marked): New action.
(helm-source-find-files): Add it in actions and reorder.
* helm-files.el (helm-ff-query-replace-in-marked-1): New.
(helm-ff-query-replace-in-marked): Use it, run in helm-run-after-quit to fix keymap.
* helm-files.el (helm-ff-query-replace-in-marked-1): Display candidates.
* helm-files.el (helm-ff-run-query-replace-in-marked): New and bind it to M-%.
* helm.el (helm-create-helm-buffer): Reinit local vars.
* helm-grep.el (helm-do-grep-1): Use helm-set-local-variable.
* helm-help.el: Update *find-files doc.
Use helm-set-local-variable in several places.
* helm-elisp.el:do it.
* helm-files.el:do it.
* helm-mode.el: do it.
* helm-help.el: Fix typo.
* helm-files.el: Rename the query-replace fn with "on-marked" instead of "in-marked".
* helm-help.el: Fix typo (on-marked).
* helm-files.el (helm-ff-query-replace-on-marked-1): Improve prompt.