[Core] Implement TeamCity output format plugin

This plugin inserts markers that can be picked up by IDEA and
Teamcity. These in turn can then use this information to display a
test tree and show the output grouped by scenario.

This is plugin is nessesary because Intelij keeps using reflection
to extract more information from the plugin system then what would
normally be available. By substituting the CucumberJvm[1-5]SMFormatter
with this plugin we avoid runtime errors.

Unfortunately the teamcity format is poorly documented[1]. Reverse
engingeering[2][3] the format from the plugin yields some information
but the exact function is rather opaque.

1. https://confluence.jetbrains.com/display/TCD9/Build+Script+Interaction+with+TeamCity#BuildScriptInteractionwithTeamCity-MessageFlowId
2. https://github.com/JetBrains/intellij-community/tree/master/plugins/cucumber-jvm-formatter5/src/org/jetbrains/plugins/cucumber/java/run
3. https://github.com/mpkorstanje/intellij-community/blob/master/plugins/cucumber-jvm-formatter/src/org/jetbrains/plugins/cucumber/java/run

Author: mpkorstanje

core/src/main/java/io/cucumber/core/options/PluginOption.java

@@ -12,6 +12,7 @@
 import io.cucumber.core.plugin.PrettyFormatter;
 import io.cucumber.core.plugin.ProgressFormatter;
 import io.cucumber.core.plugin.RerunFormatter;
+import io.cucumber.core.plugin.TeamCityPlugin;
 import io.cucumber.core.plugin.TestNGFormatter;
 import io.cucumber.core.plugin.TimelineFormatter;
 import io.cucumber.core.plugin.UnusedStepsSummaryPrinter;
@@ -44,15 +45,16 @@ public class PluginOption implements Options.Plugin {
         put("timeline", TimelineFormatter.class);
         put("unused", UnusedStepsSummaryPrinter.class);
         put("usage", UsageFormatter.class);
+        put("teamcity", UsageFormatter.class);
     }};
 
     // Refuse plugins known to implement the old API
-    private static final HashMap<String, Class<? extends Plugin>> OLD_INTELLIJ_IDEA_PLUGIN_CLASSES = new HashMap<String, Class<? extends Plugin>>() {{
-        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvmSMFormatter", PrettyFormatter.class);
-        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm2SMFormatter", PrettyFormatter.class);
-        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm3SMFormatter", PrettyFormatter.class);
-        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm4SMFormatter", PrettyFormatter.class);
-        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm5SMFormatter", PrettyFormatter.class);
+    private static final HashMap<String, Class<? extends Plugin>> INCOMPATIBLE_INTELLIJ_IDEA_PLUGIN_CLASSES = new HashMap<String, Class<? extends Plugin>>() {{
+        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvmSMFormatter", TeamCityPlugin.class);
+        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm2SMFormatter", TeamCityPlugin.class);
+        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm3SMFormatter", TeamCityPlugin.class);
+        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm4SMFormatter", TeamCityPlugin.class);
+        put("org.jetbrains.plugins.cucumber.java.run.CucumberJvm5SMFormatter", TeamCityPlugin.class);
     }};
 
     private final String pluginString;
@@ -76,9 +78,9 @@ public static PluginOption parse(String pluginArgumentPattern) {
     }
 
     private static Class<? extends Plugin> parsePluginName(String pluginName) {
-        Class<? extends Plugin> oldApiPlugin = OLD_INTELLIJ_IDEA_PLUGIN_CLASSES.get(pluginName);
+        Class<? extends Plugin> oldApiPlugin = INCOMPATIBLE_INTELLIJ_IDEA_PLUGIN_CLASSES.get(pluginName);
         if (oldApiPlugin != null) {
-            log.warn(() -> "Incompatible IntelliJ IDEA Plugin detected. Falling back to pretty formatter");
+            log.debug(() -> "Incompatible IntelliJ IDEA Plugin detected. Falling back to teamcity plugin");
             return oldApiPlugin;
         }