[NaCl SDK] AppEngine: Some fixes to the new demo layout

* Use "name" instead of "id" to set iframe contents (fixes firefox)
* Set "header" element flex so it doesn't overlap the explanatory text
* Increased the max-width of the left panel; this prevents text wrapping on
  the bullet demo buttons
* Use "position: fixed" on the loading cover (so you can't scroll it)
* Change all <a> elements to use target="_blank"
* Life: s/LIfe/Life/
* SmoothLife: Change control layout, add palette switcher, new presets
* SmoothLife: Roll to 9984167
* Lua: Roll Lua to naclports rev 970

BUG=none
R=sbc@chromium.org

Review URL: https://codereview.chromium.org/67173002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233949 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 233949