Switch to new specification format

See merge request !14

The new specification format allows us to decouple specifications from
the compiler itself, making specs more modular and readable.

Expressing complicated specifications might still need the full
capabilities of Rust, and is still possible.

The PEG grammar for files is described in 'src/grammar.pest'. The PEG
format was chosen because it is relatively simple to read and modify.

The page above GICR is falsely "Reserved" in the documentation.
We now also map it.

Improve tab complete

See merge request !13

Fix as_output, separate output of GLAS and swizzles

See merge request !12

The mapping source didn't take the source offset into account

Use a readline implementation for the REPL

See merge request !11

Morello fixes

See merge request !10

Reduce strain on SMT solver using natural alignment

See merge request !9

Merge demo-related commits

See merge request !8

We treated all resources with same local length and offset as identical,
which lead to a bunch of aliasing in the page tables / JSON output.

The solution itself was not impacted.

The Morello UART is located at 0x2xxx_xxxx, which was above the previous
split at 0x1000_0000.