remove smileys, fixes #2403

.gitignore

app/controllers/admin/smileys.php

app/controllers/smileys.php

app/views/admin/smileys/edit.php

app/views/admin/smileys/index.php

app/views/admin/smileys/statistics.php

app/views/admin/smileys/upload.php

app/views/course/forum/index/_post.php

app/views/course/forum/index/_smiley_favorites.php

app/views/smileys/index.php

app/views/smileys/picker.php

config/config.inc.php.dist

config/config_develop.inc.php

db/migrations/5.4.1_remove_smileys.php

lib/classes/ForumEntry.php

lib/classes/Markup.class.php

lib/classes/Smiley.php

lib/classes/SmileyFavorites.php

lib/classes/SmileyFormat.php

lib/classes/UserManagement.class.php