feat: get information about a given certificate

Read the domain name from the CLI, and get and print information about
the certificate to STDOUT.

The output looks like this:
```
> ./target/debug/x509-info badssl.com
        Subject: CN=*.badssl.com O= L=
        Issuer:  CN=R3 O=Let's Encrypt L=
        DNS Names: *.badssl.com, badssl.com
        Validity Period
                Not before: 2022-08-12T07:57:46-07:00
                Not After:  2022-11-10T06:57:45-08:00
```

1 files changed, 126 insertions, 0 deletions

diff --git a/src/x509-info/flake.lock b/src/x509-info/flake.lock
new file mode 100644
index 0000000..610cec8
--- /dev/null
+++ b/src/x509-info/flake.lock
@@ -0,0 +1,126 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1659877975,
+        "narHash": "sha256-zllb8aq3YO3h8B/U0/J1WBgAL8EX5yWf5pMj3G0NAmc=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "c0e246b9b83f637f4681389ecabcb2681b4f3af0",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_2": {
+      "locked": {
+        "lastModified": 1659877975,
+        "narHash": "sha256-zllb8aq3YO3h8B/U0/J1WBgAL8EX5yWf5pMj3G0NAmc=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "c0e246b9b83f637f4681389ecabcb2681b4f3af0",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "naersk": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      },
+      "locked": {
+        "lastModified": 1662220400,
+        "narHash": "sha256-9o2OGQqu4xyLZP9K6kNe1pTHnyPz0Wr3raGYnr9AIgY=",
+        "owner": "nmattia",
+        "repo": "naersk",
+        "rev": "6944160c19cb591eb85bbf9b2f2768a935623ed3",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nmattia",
+        "repo": "naersk",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1666215963,
+        "narHash": "sha256-+kSNzDXqoEVEryrJ9WrvGSvi784xPMXkk7jTJPFdT/k=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "e66821278399ba9565178ce3b525e72275fe004e",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1666229941,
+        "narHash": "sha256-0e6aB1+ZqKuQdyjwgHltHlWMYJZCn6b0gYxdTSfIKCE=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "d3c2379d149073e53eb5580deafad475c1cabe28",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1665296151,
+        "narHash": "sha256-uOB0oxqxN9K7XGF1hcnY+PQnlQJ+3bP2vCn/+Ru/bbc=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "14ccaaedd95a488dd7ae142757884d8e125b3363",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "naersk": "naersk",
+        "nixpkgs": "nixpkgs_2",
+        "rust-overlay": "rust-overlay"
+      }
+    },
+    "rust-overlay": {
+      "inputs": {
+        "flake-utils": "flake-utils_2",
+        "nixpkgs": "nixpkgs_3"
+      },
+      "locked": {
+        "lastModified": 1666234887,
+        "narHash": "sha256-WZ13mLYvByYlZKz6Q8pufvi+E3Hwo92fMKA2Kw02hRA=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "dd334e95eb46e79e52a75c80ef9ba73c3d867840",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}