Support Strikethrough with Height attribute in markup

Support Strikethrough with Height attribute in markup

The attribute of strikethrough in <s> tag :
  - height

The attribute of strikethrough in <span> tag :
  - s-height

How to apply it in TextEditor:

  textEditor.SetProperty(Dali::Toolkit::TextEditor::Property::TEXT, "<span s-color='blue' s-height='5.0f' > hello world span tag</span>nothing<s color='green' height='2.0f' > hello world s tag </s> ");
  textEditor.SetProperty(Dali::Toolkit::TextEditor::Property::ENABLE_MARKUP, true);

This patch should be preceded by the patch below:
https://review.tizen.org/gerrit/c/platform/core/uifw/dali-toolkit/+/272017

Change-Id: I3332531528f53e9bc87c6bf194fb6c58d131a269