chore: add minimum flagd provider doc

Signed-off-by: Todd Baert <toddbaert@gmail.com>

providers/flagd/README.md

@@ -0,0 +1,24 @@
+# flagd-web Provider for OpenFeature
+
+![Experimental](https://img.shields.io/badge/experimental-breaking%20changes%20allowed-yellow)
+
+A feature flag daemon with a Unix philosophy.
+
+## Installation
+
+```xml
+<dependency>
+  <groupId>dev.openfeature.contrib.providers</groupId>
+  <artifactId>flagd</artifactId>
+  <version>0.5.0</version>
+</dependency>
+```
+
+## Usage
+
+The `FlagdProvider` communicates with flagd via the gRPC protocol. Instantiate a new FlagdProvider instance, and configure the OpenFeature SDK to use it:
+
+```java
+FlagdProvider provider = new FlagdProvider("http", "localhost", 8013);
+OpenFeatureAPI.getInstance().setProvider(provider);
+```