Make a structure for frontend visualizer

Created visualizer module in compiler. It will contain basic tests for renderer. Additionally added three different modules in visualizer:
1) psi - will contain renderer for old frontend
2) fir - renderer for new frontend
3) common - will contain common code for both renderers

compiler/visualizer/common/build.gradle.kts

@@ -0,0 +1,13 @@
+plugins {
+    kotlin("jvm")
+}
+
+dependencies {
+    compile(project(":compiler:frontend"))
+    compileOnly(intellijCoreDep()) { includeJars("intellij-core") }
+}
+
+sourceSets {
+    "main" { projectDefault() }
+    "test" { }
+}