* org.el (org-trim): Rewrite and make a defsubst.
* org-bibtex.el (org-bibtex-get): Use `org-trim' instead of
`org-babel-trim'.
* ob-core.el (org-babel-trim): Delete and alias to `org-trim'.
(org-babel-chomp): Delete and alias to `org-trim-trailing'.
(org-trim-trailing): New defsubst.
(org-babel-examplize-region): Fix version.