New: Added menu Create Project... in xCodeCapp

Previously it wasn't possible to create a capp project from xCodeCapp.
Now you can create one from the menu item Create Project, xCodeCapp will load the project as the same time is no error occurs.
When choosing an existing project, xCodeCapp removes the old one (this is asked to the user, would you like to replace the files...).
In case of errors, the errors panel appears.
Added: Creating project with symlinks

Previously it wasn't possible to create project with symlink.
Now you can set in the preferences of xCodeCapp if you want to create your project with symlink or not with a radioButton.
When launching xCodeCapp, the system will check if $CAPP_BUILD is defined or not. If not, the button in the preference will be disabled and a toolTip will advice how to create a $CAPP_BUILD variable.
Changed capp_buid to cap_build....
Changed the format of the xib to 4.6
Merge pull request #1969 from Dogild/xCodeCappCreateProject

New: Added menu Create Project... in xCodeCapp