babel: evaluation of code blocks now requires confirmation
* lisp/babel/ob.el (org-confirm-babel-evaluate): variable used to
control evaluation of code blocks, default value it t, meaning all
code block evaluation requires confirmation
(org-babel-confirm-evaluate): function used to request confirmation
of code block evaluation from the user
(org-babel-execute-src-block): this function is the single point of
entry for evaluation of code blocks (whether initiated through lob
call, through direct code block evaluation, or as part of file
exportation). Every time this function is called it will now
request confirmation from the user. The newly added
`org-confirm-babel-evaluate' variable can be used to configure this
behavior.
(org-babel-no-eval-on-ctrl-c-ctrl-c): This variable can be used to
inhibit evaluation of code blocks with C-c C-c.
* lisp/org.el (org-ctrl-c-ctrl-c): added documentation of code block
evaluation behavior
* lisp/babel/ob-keys.el (org-babel-key-bindings): adding keybindings
for executing code blocks and for opening their results