Keyboard shortcut changes

[ellisonbg]

We plan on making the following changes to the keyboard shortcuts:

• Leave ctrl+j and ctrl+k for move up/down
• Save shift+j/k for contiguous selection
• Use v and shift+V for paste below and above
• Use r for raw cells
• Use 00 for restart kernel
• Use ii for interrupt kernel
• Look into KeyboardShortcut width and height in css
• Fix help string of shift+o
• Add shift+m for merge below in addition to shift+=
• Leave alt+- for split cell
• List CodeMirror keyboard shortcuts in edit mode Shortcut help.
• Accept cmd in place of meta on OS X.
• Show cmd in place of meta in help - internally still use meta.
• Add IPython.utils.platform.
• Conditionally define shortcuts using cmd on OS X.

[ivanov]

Add a checkbox to changing a cell type should not enter edit mode (as per my recollection of the dev meeting discussion). @matthew-brett‎ ran into this today and found it highly confusing.

[ellisonbg]

Ahh, that is going to be in a separate PR/issue about the actual behaviors: #4885

[ellisonbg]

Closed by #4894