Add support for OpenSergo TrafficRouter CRD v1alpha1 (#32)

* Design of the route proto: we just leveraged the original "route configuration" from xDS RDS proto (and there are some extension fields inside it, which may satisfy our requirement)
* feat: add route_fallback.pb.go
* feat: Add logic for watching and transforming TrafficRouter CRD
* refactor: ignore all files in IDEA directory

Co-authored-by: panxiaojun233 <[email protected]>
Co-authored-by: Liu Ziming

.gitignore

@@ -3,75 +3,28 @@
 # Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
 # Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
 
-# User-specific stuff
-.idea/**/workspace.xml
-.idea/**/tasks.xml
-.idea/**/usage.statistics.xml
-.idea/**/dictionaries
-.idea/**/shelf
-
-# Generated files
-.idea/**/contentModel.xml
-
-# Sensitive or high-churn files
-.idea/**/dataSources/
-.idea/**/dataSources.ids
-.idea/**/dataSources.local.xml
-.idea/**/sqlDataSources.xml
-.idea/**/dynamic.xml
-.idea/**/uiDesigner.xml
-.idea/**/dbnavigator.xml
-
-# Gradle
-.idea/**/gradle.xml
-.idea/**/libraries
-
-# Gradle and Maven with auto-import
-# When using Gradle or Maven with auto-import, you should exclude module files,
-# since they will be recreated, and may cause churn.  Uncomment if using
-# auto-import.
-# .idea/artifacts
-# .idea/compiler.xml
-# .idea/jarRepositories.xml
-# .idea/modules.xml
-# .idea/*.iml
-# .idea/modules
-# *.iml
-# *.ipr
+.idea/
+.idea_modules/
+*.iml
 
 # CMake
 cmake-build-*/
 
-# Mongo Explorer plugin
-.idea/**/mongoSettings.xml
-
 # File-based project format
 *.iws
 
 # IntelliJ
 out/
 
-# mpeltonen/sbt-idea plugin
-.idea_modules/
-
 # JIRA plugin
 atlassian-ide-plugin.xml
 
-# Cursive Clojure plugin
-.idea/replstate.xml
-
 # Crashlytics plugin (for Android Studio and IntelliJ)
 com_crashlytics_export_strings.xml
 crashlytics.properties
 crashlytics-build.properties
 fabric.properties
 
-# Editor-based Rest Client
-.idea/httpRequests
-
-# Android studio 3.1+ serialized cache file
-.idea/caches/build_file_checksums.ser
-
 ### macOS template
 # General
 .DS_Store