small edits to text editor from writing a python editor extension.

- rename TextLine.line -> body, ConsoleLine.line -> body
- minor speedups when setting the body text, also re-allocate console lines if they are < half the length.
- added option to highlight current line in the text editor.

release/scripts/op/console_shell.py

@@ -47,7 +47,7 @@ def execute(context):
     sc = context.space_data
 
     try:
-        line = sc.history[-1].line
+        line = sc.history[-1].body
     except:
         return {'CANCELLED'}