fix: internal links break with &, | chars

[londonsangongzi]

This PR fixes an issue(#133) where internal links containing & and | characters, such as [[A & B]], [[A & B|AB]], [AB](<A & B.md>).

[james-tindal]

Could you make a few minor style changes please?

• Replace var with let
• Remove line 26 - commented out const url...
• Single space after each //
• if statement spacing like this: if () {} else {}

[londonsangongzi]

I've finished the style changes which are now available in pr for review, thanks.

Jeff