bootloader: get rid of source copying, build directly from the source instead

See merge request !401

init: update init.rc to use set-default-scheme

See merge request redox-os/cookbook!397

[WIP] Initial Dropbear Port/Build.

See merge request !399

Add the PopOS wallpapers recipe

See merge request !366

Add the Ubuntu wallpapers recipe

See merge request !365

Add Path variant to SourceRecipe

See merge request !396

Better TODOs for sqlite3.

See merge request !395

Also:
* rustfmt

Fix and clean up the perl5 recipe.

See merge request !393

Remove the -Csoft-float argument when building the kernel

See merge request !392

The targets specify the soft-float ABI already and -Csoft-float should likely
have never existed in the first place. It is unsound to mix crates compiled
with different float ABI's and the only stable way to get all crates to agree
on the soft float ABI is by specifying a target which uses the soft float ABI
anyway even without explicit -Csoft-float.

See also https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/.60-Csoft-float.60.20considered.20harmful

Update GNU make to v4.4 and create new recipe and new patch.

See merge request !390