merge with master

diff --cc Cargo.lock
index 526c4fc7a46908815bfe7327255f924d1d3618b7,090acbf522b236dfd40893a10572761e6d4bc35f..01f168304b4f3840e1da01ebdb2722c0352d8c79
--- 1/Cargo.lock
--- 2/Cargo.lock
+++ b/Cargo.lock
@@@ -442,9 -467,17 +467,17 @@@ dependencies = 
   "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  ]
  
+ [[package]]
+ name = "proc-macro2"
+ version = "1.0.9"
+ source = "registry+https://github.com/rust-lang/crates.io-index"
+ dependencies = [
+  "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ ]
+ 
  [[package]]
  name = "prolog_parser"
 -version = "0.8.47"
 +version = "0.8.49"
  source = "registry+https://github.com/rust-lang/crates.io-index"
  dependencies = [
   "lexical 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@@ -790,9 -849,12 +849,11 @@@ dependencies = 
  "checksum ordered-float 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7eb5259643245d3f292c7a146b2df53bba24d7eab159410e648eb73dc164669d"
  "checksum parking_lot 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "92e98c49ab0b7ce5b222f2cc9193fc4efe11c6d0bd4f648e374684a6857b1cfc"
  "checksum parking_lot_core 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7582838484df45743c8434fbff785e8edf260c28748353d44bc0da32e0ceabf1"
+ "checksum proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)" = "fcfdefadc3d57ca21cf17990a28ef4c0f7c61383a28cb7604cf4a18e6ede1420"
  "checksum proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)" = "cf3d2011ab5c909338f7887f4fc896d35932e29146c12c8d01da6b22a80ba759"
 -"checksum proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)" = "6c09721c6781493a2a492a96b5a5bf19b65917fe6728884e7c44dd0c60ca3435"
 -"checksum prolog_parser 0.8.47 (registry+https://github.com/rust-lang/crates.io-index)" = "2cf575fc8b91b2d9a9487f13655cffb6f697a5294b74de9b24b6a5fbe987e229"
 +"checksum prolog_parser 0.8.49 (registry+https://github.com/rust-lang/crates.io-index)" = "82f46113e58039861f82f6b6cdaca94c0997eda2c7317a4c4f13d549c4601eec"
  "checksum quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)" = "6ce23b6b870e8f94f81fb0a363d65d86675884b34a09043c81e5562f11c1f8e1"
+ "checksum quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2bdc6c187c65bca4260c9011c9e3132efe4909da44726bad24cf7572ae338d7f"
  "checksum rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6fdeb83b075e8266dcc8762c22776f6877a63111121f5f8c7411e5be7eed4b"
  "checksum rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9c33a3c44ca05fa6f1807d8e6743f3824e8509beca625669633be0acbdf509dc"
  "checksum rand_os 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "7b75f676a1e053fc562eafbb47838d67c84801e38fc1ba459e8f180deabd5071"

diff --cc Cargo.toml
Simple merge