add a README.md

Author: Alvaro Muñoz

README.md

@@ -0,0 +1,74 @@
+
+### gh-qldb
+
+Tired of having dozens of CodeQL databases scattered around your file system? Introducing QLDB, a CodeQL database manager. Download, deploy and create CodeQL databases with ease.
+
+QLDB will organize your databases in a hierarchical structure:
+
+```
+/Users/pwntester/codeql-dbs
+└── github.com
+   ├── apache
+   │  ├── logging-log4j2
+   │  │  ├── java
+   │  │  │  └── fa2f51eb8d5912b92b8aa75693464f3e55d36be9.zip
+   │  │  └── javascript
+   │  │     └── abf13fabc45a2f51eb8d5912b92b8aa75693464f.zip
+   │  └── commons-text
+   │     └── java
+   │        └── e2b291e92bcc272f98d6ca6723994da985d30e07.zip
+   └── pwntester
+      └── sample-project
+         └── java
+            └── 9b84404246d516a11091e74ef4cdcf7dfcc63fa4.zip
+```
+
+### Usage
+
+```
+Usage:
+  gh qldb [command]
+
+Available Commands:
+  completion  Generate the autocompletion script for the specified shell
+  create      Extracts a CodeQL database from a source path
+  download    Downloads a CodeQL database from GitHub Code Scanning
+  help        Help about any command
+  install     Install a local CodeQL database in the QLDB directory
+  path        Returns the path to a database stored in the QLDB structure
+
+Flags:
+  -h, --help   help for gh-qldb
+```
+
+### Examples:
+
+#### Create a database
+
+```bash
+gh qldb -n foo/bar -- -s path/to/src -l java
+```
+
+#### Download a Code Scanning database
+
+```bash
+gh qldb download -n apache/logging-log4j2 -l java
+```
+
+#### Install a local database in QLDB structure
+
+```bash
+gh qldb install -d path/to/database -n apache/logging-log4j2
+```
+
+#### Get information about a database
+
+```       
+gh qldb path -n apache/logging-log4j2 -l java -j
+[
+  {
+    "commitSha": "fa2f51e",
+    "committedDate": "2023-04-06T06:25:30",
+    "path": "/Users/pwntester/codeql-dbs/github.com/apache/logging-log4j2/java/9b84404246d516a11091e74ef4cdcf7dfcc63fa4.zip
+  }
+]                                                                                                                                                                                                                                                                                                                                                                                       ```