Add Composer to table of supported schemes

Signed-off-by: Niklas <nscuro@protonmail.com>

Author: nscuro

README.md

@@ -15,6 +15,7 @@ Java implementation of [vers](https://github.com/package-url/purl-spec/blob/vers
 | Scheme   | Supported |
 |:---------|:---------:|
 | APK      |     ✅     |
+| Composer |     ✅     |
 | CPAN     |     ❌     |
 | Debian   |     ✅     |
 | Ruby Gem |     ❌     |
@@ -214,4 +215,4 @@ To add support for a new scheme, let's say `alpine`, the following steps may be
 6. List the fully qualified package name of all custom `VersionProvider` implementations, one per line
     * e.g. `com.acme.AlpineVersionProvider`
 
-That's it! Now, whenever *versatile* encounters a `vers` range with the scheme `alpine`, it will use your `AlpineVersion`!
+That's it! Now, whenever *versatile* encounters a `vers` range with the scheme `alpine`, it will use your `AlpineVersion`!