Improve options generation README and picky directory refacto

docs/spec/cmdline-opts-hurl/README

@@ -1,8 +0,0 @@
-# Format all option files
-bin/spec/cmdline-opts/format.py docs/spec/cmdline-opts-hurl/*.option
-
-# Generate/Update clap command source file
-bin/spec/cmdline-opts/generate_source.py docs/spec/cmdline-opts-hurl/*.option >packages/hurl/src/cli/options/commands.rs
-
-# Generate/Update man options
-bin/spec/cmdline-opts/generate_man.py docs/spec/cmdline-opts-hurl/*.option

docs/spec/options/README.md

@@ -0,0 +1,31 @@
+# Command Line Options
+
+Hurl command line options are described with `.option` files. These files are used to generate:
+
+- Rust code to parse this options in `hurl`/`hurlfmt` packages
+- Man options
+
+
+## Format all option files
+
+```shell
+$ bin/spec/options/format.py docs/spec/options/**/*.option
+```
+
+This script insures that all `.option` files are well formatted.
+
+## Generate/Update clap command source file
+
+```shell
+$ bin/spec/options/generate_source.py docs/spec/options/hurl/*.option > packages/hurl/src/cli/options/commands.rs
+```
+
+This script generates Rust source file for parsing command line option.
+
+## Generate/Update man options
+
+```shell
+$ bin/spec/options/generate_man.py docs/spec/options/hurl/*.option
+```
+
+This script generates (part of) man file for `hurl` / `hurlfmt`.