Add href prop

With the href prop, one can use <Obfuscate> in a similar manner as using the <a> tag. Thank you to @anantoghosh for requesting this feature at #37.

<Obfuscate href="https://wa.me/15551234567">Chat On WhatsApp</Obfuscate>

• Merge pull request #38 from coston/obfuscate-href-prop-#37 9a7e858
• Update href demo fa2f6d5
• Add href prop 7048262

v3.4.0-0...v3.4.0