WIP: Add basic support for text-transform

[ngthailam]

Add support for text-transformation for #642

Changes:

• Add code for basic text-transformation: capitalize, uppercase, lowercase, none
• Add related UTs

Notes:

I am doing the basic implementation first, so these features are not supported yet.

• Have NOT check support for multi language.
• Have NOT support other text-transformation(s) yet.

[ngthailam]

@daohoangson Can you provide me with some guidance on this, I am having some trouble:

• p, center, h123456 tags works with text-transform
• However some tags like abbr or blockquote, the CssTextTransform cannot be found in the InheritedProperties. These tags works with text-transform on the Web.

I m trying to debug the root cause but it is quite complicated as I dont know the system well.
Would you have an idea on this ?

[daohoangson]

Text transform may be complicated than this. It must work across different tags, e.g. <p style="text-transform: capitalize">h<em>el</em>lo w<strong>orl</strong>d</p>...

[ngthailam]

Let me look more into this then