r2dbc#242 OSGi headers

Inclusion of optional ServiceLoader provider requirement

Author: ascertrobw

r2dbc-spi/pom.xml

@@ -86,7 +86,7 @@
                             <Bundle-Version>${project.version}</Bundle-Version>
                             <Export-Package>io.r2dbc.spi;version="${project.version}"</Export-Package>
                             <Import-Package>javax.annotation.meta;resolution:=optional,javax.annotation</Import-Package>
-                            <Require-Capability>osgi.ee;filter:="(&amp;(osgi.ee=JavaSE)(version=1.8))"</Require-Capability>
+                            <Require-Capability>osgi.ee;filter:="(&amp;(osgi.ee=JavaSE)(version=1.8))", osgi.extender;resolution:=optional;filter:="(osgi.extender=osgi.serviceloader.processor)",osgi.serviceloader;resolution:=optional;filter:="(osgi.serviceloader=io.r2dbc.spi.ConnectionFactoryProvider)";cardinality:=multiple</Require-Capability>
                         </manifestEntries>
                     </archive>
                 </configuration>