Emojis are huge when viewed on some markdown renderers

[rubiefawn]

Describe the issue
Some markdown renderers sanitize the style attribute within inline HTML, causing the emoji SVGs to appear at full size rather than match the text size.

[rubiefawn]

Adding an additional height="18" before the style attribute could provide a simple fallback in the case the output HTML gets sanitized.

Status:

• Github Fallback works correctly
• Typora Fallback takes precedence over style attribute
• StackEdit Fallback takes precedence over style attribute
• Editor.md Fallback takes precedence over style attribute

Unfortunately it appears that the height and width attributes take precedence over style, regardless of order.

[rubiefawn]

The solution is to solely employ the height attribute and remove style since it gets ignored.