Switch allocator to jemalloc (#3697)

## Proposed Changes

Another `tree-states` motivated PR, this adds `jemalloc` as the default allocator, with an option to use the system allocator by compiling with `FEATURES="" make`.

- [x] Metrics
- [x] Test on Windows
- [x] Test on macOS
- [x] Test with `musl`
- [x] Metrics dashboard on `lighthouse-metrics` (https://github.com/sigp/lighthouse-metrics/pull/37)


Co-authored-by: Michael Sproul <micsproul@gmail.com>

Makefile

@@ -14,8 +14,16 @@ BUILD_PATH_AARCH64 = "target/$(AARCH64_TAG)/release"
 PINNED_NIGHTLY ?= nightly
 CLIPPY_PINNED_NIGHTLY=nightly-2022-05-19
 
+# List of features to use when building natively. Can be overriden via the environment.
+# No jemalloc on Windows
+ifeq ($(OS),Windows_NT)
+    FEATURES?=
+else
+    FEATURES?=jemalloc
+endif
+
 # List of features to use when cross-compiling. Can be overridden via the environment.
-CROSS_FEATURES ?= gnosis,slasher-lmdb,slasher-mdbx
+CROSS_FEATURES ?= gnosis,slasher-lmdb,slasher-mdbx,jemalloc
 
 # Cargo profile for Cross builds. Default is for local builds, CI uses an override.
 CROSS_PROFILE ?= release
@@ -101,10 +109,6 @@ cargo-fmt:
 check-benches:
 	cargo check --workspace --benches
 
-# Typechecks consensus code *without* allowing deprecated legacy arithmetic or metrics.
-check-consensus:
-	cargo check -p state_processing --no-default-features
-
 # Runs only the ef-test vectors.
 run-ef-tests:
 	rm -rf $(EF_TESTS)/.accessed_file_log.txt