Find Usages: Classify package usages

#KT-4882 Fixed

idea/testData/findUsages/kotlin/findPackageUsages/kotlinPackageUsages.0.kt

@@ -0,0 +1,10 @@
+// PSI_ELEMENT: com.intellij.psi.PsiPackage
+// OPTIONS: usages
+// FIND_BY_REF
+package <caret>foo.bar
+
+import foo.bar.X
+
+class X
+
+val x: foo.bar.X? = foo.bar.X()

idea/testData/findUsages/kotlin/findPackageUsages/kotlinPackageUsages.results.txt

@@ -0,0 +1,4 @@
+Class/object property type (10: 8) val x: foo.bar.X? = foo.bar.X()
+Package directive (4: 9) package foo.bar
+Package member access (10: 21) val x: foo.bar.X? = foo.bar.X()
+Usage in import (6: 8) import foo.bar.X