- dependency repos moved to "vendor/<package name>"; delete
"vendor/repos" by hand after making sure it contains no unpushed work
- fixed the "validator_keygen" build and merged it with that of "beacon_node"
- replaced `nimble` with `nim` for compiling, since `nim` already knows
how to add the Nimble packages to its module path
- better target dependencies for "beacon_node" and "validator_keygen"
- isolate dependencies (both Git repos and ".nimble" dir) in "vendor"
- ensure that everything is compiled using our version of Nim with
something as simple as "make"
- pull the latest changes with "make update"
- re-create Nimble's package dir and re-build the Nim compiler automatically when needed
- "env.sh" script that can be used to prefix any command that needs to use
"nim" or "nimble" from our Nim repo
- move the top level nim.cfg to nimbus/nim.cfg so it doesn't apply to
deps
- "fetch-dlls" `make` target for Windows to get precompiled Snappy, RocksDB and SQLite DLLs
- dynamically generated copyright year interval
- added the db backend to the header
- documented the db-backend-changing define, made it case insensitive
and ensured wrong values would trigger compilation errors
- port to new APIs
- added copyright headers
- bumped the copyright interval in modified files
- fixed tests
- reorganised imports
- normalised function names
- deleted some trailing space
- added test_rpc to all_tests
- assert() -> doAssert()
- moved the RPC port in a constant for the test suite
