Add pronunciation

[muno92]

Add a description of pronunciation like runn's README.

I referred to your talk in PHPerKaigi and following pages.

• https://ejje.weblio.jp/content/tables#hideDictPrsENWIK
• http://ipa-reader.xyz/

[k1LoW]

Surely it's time to clarify the pronunciation of "tbls".

[k1LoW]

@muno92 Thank you!