Code editor
Define QSCINTILLA_DLL for windows
Use code editor for expression widget
Clean up code editor code and API. Add tr() and fix spelling.

Moved show/hide folding and margin methods to base class.
Legend refactoring: first steps towards legend customization

- map layers have associated QgsMapLayerLegend instance
- QgsMapLayerLegend is interface for generation of legend with some default implementations
- QgsLayerTreeModelLegendNode is interface for representation of legend item in layer tree model with some default implementations
[composer] More cleanups - move font utils from QgsComposerItem to QgsComposerUtils, add tests
[composer] documentation improvements
[composer] Write a dummy Grid element when saving composer maps, fixes crash when loading project in older QGIS versions (fix #10905)
[composer] Fix restoration of grid color alpha channel from 2.4 projects
[composer] Don't auto set maximum number of attributes when resizing item. Instead, keep the maximum number of rows as whatever the user set. This change prevents the attribute table from shrinking and never re-growing (fix #10911)
Merge pull request #1507 from NathanW2/code_editor

Code editor using QScintilla.

Thanks to Salvatore Larosa for the initial work.
Drop QScintilla2 from window title
[TRANSUP] common translation update

Signed-off-by: Werner Macho <werner.macho@gmail.com>