add xcode project and app for a launcher.  includes copying a distribution and jre to the Resources folder of the resulting app.
build instructions
Update README.md
copy in missing function from ../dev/build.gradle
Update README.md
use our existing beaker.command script to complete the launch.  still needs to be killed!  also moved to app init instead of document.
merge
remove leftover unused experimental code
add files for main app delegate, add copyright header
another copyright header
set DYLD_LIBRARY_PATH in PluginServiceLocatorRest.java instead of in the launcher script.  set up the JAVA_HOME envar in the native launcher.
move launching beaker to app delegate, add closing the task on app exist
prevent the application from opening a blank untitled document every time.  we want documents but only if the user double clicks them.
use special nginx env (with DYLD_LIBRARY_PATH defined on mac) for restarting nginx as well as starting it.
on mac, insert extra layer of bash with the login option so that the .bash_profile gets read (this is where anaconda alters the PATH to find ipython).  consolidate how auxiliary ipython programs are launched.
bump travis
ignore xcuserdata, which are user preferences not part of the project
remove existing xcuserdata
Merge pull request #361 from twosigma/launcher

Launcher
Move code-cell behaviors according to design

Implements a basic version of the codecell styling
that does not remove any functionality however brings it closer
inline with the implemented design.