Trim down dependencies some more

With the same goal of removing dependencies, removing regex from env_logger (which is not being used), as well as removing the regex Cargo features that we are not using at build time, we can drop two external crates from the build.

Cargo.lock

@@ -1,13 +1,5 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-[[package]]
-name = "aho-corasick"
-version = "0.7.10"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "ansi_term"
 version = "0.11.0"
@@ -174,7 +166,6 @@ dependencies = [
  "atty 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "humantime 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "termcolor 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -619,10 +610,7 @@ name = "regex"
 version = "1.3.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "aho-corasick 0.7.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex-syntax 0.6.17 (registry+https://github.com/rust-lang/crates.io-index)",
- "thread_local 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -724,14 +712,6 @@ dependencies = [
  "winapi-util 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "thread_local"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "time"
 version = "0.1.43"
@@ -865,7 +845,6 @@ dependencies = [
 ]
 
 [metadata]
-"checksum aho-corasick 0.7.10 (registry+https://github.com/rust-lang/crates.io-index)" = "8716408b8bc624ed7f65d223ddb9ac2d044c0547b6fa4b0d554f3a9540496ada"
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 "checksum ansi_term 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d52a9bb7ec0cf484c551830a7ce27bd20d67eac647e1befb56b0be4ee39a55d2"
 "checksum async-trait 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)" = "26c4f3195085c36ea8d24d32b2f828d23296a9370a28aa39d111f6f16bef9f3b"
@@ -947,7 +926,6 @@ dependencies = [
 "checksum syn 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)" = "f14a640819f79b72a710c0be059dce779f9339ae046c8bef12c361d56702146f"
 "checksum tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e24d9338a0a5be79593e2fa15a648add6138caa803e2d5bc782c371732ca9"
 "checksum termcolor 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bb6bfa289a4d7c5766392812c0a1f4c1ba45afa1ad47803c11e1f407d846d75f"
-"checksum thread_local 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
 "checksum time 0.1.43 (registry+https://github.com/rust-lang/crates.io-index)" = "ca8a50ef2360fbd1eeb0ecd46795a87a19024eb4b53c5dc916ca1fd95fe62438"
 "checksum tokio 0.2.21 (registry+https://github.com/rust-lang/crates.io-index)" = "d099fa27b9702bed751524694adbe393e18b36b204da91eb1cbbbbb4a5ee2d58"
 "checksum tokio-tls 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9a70f4fcd7b3b24fb194f837560168208f669ca8cb70d0c4b862944452396343"

Cargo.toml

@@ -42,12 +42,16 @@ serde = "1.0"
 serde_json = "1.0"
 
 # logging
-env_logger = "0.7"
 log = "0.4"
 
+[dependencies.env_logger]
+version = "0.7"
+default_features = false
+features = [ "termcolor", "atty", "humantime" ]
+
 [build-dependencies]
 datetime = { version = "0.5.1", default_features = false }
-regex = "1.3"
+regex = { version = "1.3", default_features = false, features = ["std"] }
 
 [dev-dependencies]
 pretty_assertions = "0.6"