Refactor populateInputs method

* Now accepts Collection instead of just Set
* Renamed to populateInputCandidates for clarity

Author: hinerm

src/main/java/org/scijava/convert/AbstractConverter.java

@@ -31,7 +31,7 @@
 
 package org.scijava.convert;
 
-import java.util.Set;
+import java.util.Collection;
 
 import org.scijava.plugin.AbstractHandlerPlugin;
 
@@ -83,7 +83,7 @@ public Object convert(final ConversionRequest request) {
 	}
 
 	@Override
-	public void populateInputs(Set<Object> objects) {
+	public void populateInputCandidates(final Collection<Object> objects) {
 		// No-op
 	}
 

src/main/java/org/scijava/convert/DefaultConvertService.java

@@ -107,7 +107,7 @@ public Collection<Object> getCompatibleInputs(Class<?> dest) {
 
 		for (final Converter c : getInstances()) {
 			if (dest.isAssignableFrom(c.getOutputType())) {
-				c.populateInputs(objects);
+				c.populateInputCandidates(objects);
 			}
 		}