Support assembly blocks

At the moment, `pasfmt` vehemently ignores inline assembly blocks. It understands their structure well enough to parse them, but then ignores the block and all of its statements.

It is generally assumed that users format inline assembly in a way that makes it easiest for them to read. Given this, `pasfmt` formatting these blocks would counterproductive and undesirable. This is why it was decided to ignore assembly blocks altogether.

Inline assembly support might introduce features such as:
* Token spacing
* Indentation
* Operand alignment

These features would be gated behind a user-facing setting, allowing users to opt in.