Minor changes to app

[cormacanderson]

Following a number of avoidable misunderstandings in a recent review, I would propose the following minor changes to be made to the app:

1. Prominently add an IPA pronunciation for CLTS, as in the read.md here
2. For the pages for individual sounds, e.g. https://clts.clld.org/parameters/voiceless_dental_click_consonant, specify which sounds are aliases, perhaps by mentioning this in brackets after the dataset, i.e. bipa (alias)