margins and padding fixes for plugins

boyan.bootstrap.file-tree
boyan.bootstrap.new-project-dialog
boyan.bootstrap.menu addMenuItem changes

Now position of menu item can be specified using
menu.addMenuItem("Test", 1, function () {});
where 1 is the position of menu item
boyan.presentation.impress.about improvements

added createProjectFunction argument to
boyan.bootstrap.new-project-dialog
fixes for .travis.yml