Network constants diversity

[OlivierBBB]

We need a solution to handle network constants for various networks, e.g.

• CHAINID
• BASEFEE
• BLOCK_GAS_LIMIT
• (before decentralization) COINBASE address

as well as for contexts where some of these hard-coded constants make no sense (Ethereum test suite.)

Several solutions are conceivable:

• have several <network-name>-config.lisp files e.g. mainnet-config.lisp, sepolia-config.lisp, reference-tests-config.lisp and maybe adding build commands à la make mainnet-zkevm.bin
• using a single ZKEVM_MODULES list and adding an option to the make zkevm.bin command to include the correct config constants file and producing the associated <network-name>-zkevm.bin file
• not having such files in the project but generating them on the fly (there are only a few such files and they are short) when compiling the zkevm.bin

[DavePearce]

For this issue, it looks like the first approach has been adopted for building the zkevm.bin file for the reference tests. However, they don't specialise the constants (though they could easily).