Turn off unneeded lint rules

[mattleff]

Refs https://github.com/bountonw/translate/pull/292.

[mattleff]

@bountonw We can target this change more specifically, but I'm not sure that we really care about either of these lint rules:

1. no-emphasis-as-heading bans all lines composed entirely of emphasized text (*whatever sentence*, or **whatever sentence**). But, obviously, there could be legitimate cases where that is wanted, so it doesn't seem like a global ban makes sense.
2. first-line-heading requires that the first line in any markdown file is a heading/h1. We don't want this. We already avoid this in all the other files because we use a yaml header. So this rule can be off always, in my opinion.

What do you think?

[bountonw]

@bountonw We can target this change more specifically, but I'm not sure that we really care about either of these lint rules:

1. no-emphasis-as-heading bans all lines composed entirely of emphasized text (*whatever sentence*, or **whatever sentence**). But, obviously, there could be legitimate cases where that is wanted, so it doesn't seem like a global ban makes sense.
2. first-line-heading requires that the first line in any markdown file is a heading/h1. We don't want this. We already avoid this in all the other files because we use a yaml header. So this rule can be off always, in my opinion.

What do you think?

Ok. Sounds good