Some renames and javadoc.

src/main/java/net/rubygrapefruit/platform/internal/TerminfoTerminals.java

@@ -0,0 +1,27 @@
+package net.rubygrapefruit.platform.internal;
+
+import net.rubygrapefruit.platform.Terminal;
+import net.rubygrapefruit.platform.Terminals;
+import net.rubygrapefruit.platform.internal.jni.PosixTerminalFunctions;
+
+public class TerminfoTerminals implements Terminals {
+    private static Output currentlyOpen;
+    private static TerminfoTerminal current;
+
+    public boolean isTerminal(Output output) {
+        return PosixTerminalFunctions.isatty(output.ordinal());
+    }
+
+    public Terminal getTerminal(Output output) {
+        if (currentlyOpen != null && currentlyOpen != output) {
+            throw new UnsupportedOperationException("Currently only one output can be used as a terminal.");
+        }
+        if (current == null) {
+            current = new TerminfoTerminal(output);
+            current.init();
+        }
+
+        currentlyOpen = output;
+        return current;
+    }
+}