rework on UILineEdit

* allow multiline text editing
* rename UILineEdit to UITextEdit

modules/core_styles/styles/textedits.otui

@@ -0,0 +1,17 @@
+TextEdit < UITextEdit
+  font: verdana-11px-antialised
+  color: #aaaaaa
+  size: 86 20
+  text-offset: 0 3
+  text-margin: 3
+  image-source: /core_styles/styles/images/panel_flat.png
+  image-border: 1
+
+  $disabled:
+    color: #aaaaaa88
+
+PasswordTextEdit < TextEdit
+  text-hidden: true
+
+MultilineTextEdit < TextEdit
+  multiline: true