Add internal command to render CLI usage text for manual

Cargo.lock

@@ -11,6 +11,16 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "ansi-to-html"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19ee82de0545b181a17cbdef44fce80ecaf394e001da7ea279008bf2e0944bee"
+dependencies = [
+ "regex",
+ "thiserror",
+]
+
 [[package]]
 name = "ansi_term"
 version = "0.11.0"
@@ -112,6 +122,7 @@ dependencies = [
 name = "colmena"
 version = "0.1.0"
 dependencies = [
+ "ansi-to-html",
  "async-trait",
  "atty",
  "clap",
@@ -781,6 +792,26 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "thiserror"
+version = "1.0.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "854babe52e4df1653706b98fcfc05843010039b406875930a70e4d9644e5c417"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "1.0.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aa32fd3f627f367fe16f893e2597ae3c05020f8bba2666a4e6ea73d377e5714b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "tinyvec"
 version = "1.5.0"