Implement Block GET/PUT with new schema

- `Arc`+`Mutex` is replaced by `parking_lot::RwLock,` decoupled
  Read+Write and ability to upgrade read locks into write locks if
  needed
- Schema has changed, `Db` is now a struct that implements `new()` to
  return a new instance of itself, pros/cons listed in code but tl;dr
  blockchain and pending transactions are separate now
- `custom_filters` now supports extracting Block json and Transaction
  json in separate functions too
- /block GET and PUT implemented, `Blocks` currently have one check
  (transactions appear in pending transaction)
- debug is working after something, dunno how I fixed it

1 files changed, 1 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 3f9c00d..a203a6f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,6 +13,7 @@ serde = { version = "1.0.104", features = ["derive"] }
 chrono = { version = "0.4.10", features = ["serde"] }
 log = "0.4.8"
 pretty_env_logger = "0.3.1"
+parking_lot = "0.10.0"
 
 [dev-dependencies]
 serde_json = "1.0.44"