Add csi clear the entire screen 2J


git-svn-id: svn+ssh://svnrepo/projects/tachyon/trunk@7266 561c3618-0fe6-0310-b5d6-fc65c73fee30
Introduce a helper to compare a constant string against a dynamic string


git-svn-id: svn+ssh://svnrepo/projects/tachyon/trunk@7268 561c3618-0fe6-0310-b5d6-fc65c73fee30
Fix test by taking into account the new clean screen at start


git-svn-id: svn+ssh://svnrepo/projects/tachyon/trunk@7269 561c3618-0fe6-0310-b5d6-fc65c73fee30