EComposerPrivate - Fix compilation warnings
EEditorSelection - Fix detection of Blockquote block format
EEditorSelection - Refactorization
EEditorWidget - Always put text in some paragraph
EEditorSelection - When unindenting force the spell check
EEditorWidget - When changing composer mode, change paragraphs style as well

In plain text mode (Normal paragraph format) we are limiting the width
of the paragraph. In HTML mode we have to remove these limits.