Merge pull request #671 from tuhdo/exp

Fix a bug where Semantic buffer is empty
* helm-buffers.el: Show action in buffer action properly (#674).
* helm-semantic.el: Rename some symbols.
(helm-semantic--tags-cache): from helm-semantic-tags.
(helm-semantic--fetch-candidates): from helm-semantic-init-candidates
* helm-eval.el: Fix keymap conflict with tab.
* helm-source.el: Attempt to fix (#672).
(helm--setup-source): Ensure symbols are quoted.
* helm-files.el (helm-ff-cache-add-file): Allow using wild-card.
Merge branch 'master' into exp
* helm-files.el (helm-substitute-in-filename): Fix docstring.
* helm-mode.el: Allow disabling completion-in-region in modes (#673).
(helm-mode-no-completion-in-region-in-modes): New user var.
(helm--completion-in-region): Use it.
* helm-mode.el (helm-comp-read): Allow adding a transformer to hist source.
Use helm-source for source history.
* helm-command.el: Use it.
* helm-mode.el (helm-comp-read): Use helm-source to build src and src1.
* helm-source.el: Indent 1 in build macros.
* helm-mode.el: Reindent.
* helm-command.el: Don't sort history candidates.