build: Add runtime components to devel target too

The devel target needs components in the runtime target, otherwise
the composed tree will only have development tools.
build: Don't reuse cached initramfs for live target

We will build a new initramfs during images generation because we need
a special initramfs image.
build: Cleanup

Replace single quotes with double quotes.
task: Keep elapsed-millis decimals

It's more precise.