Cleanup the CollectEntryPoints mess

We had two slightly different copies of the files:
- the object in jvm/CEP is used in the backend, the class is unused
- the class in transform/CEP is used as a compiler phase, however it
doesn't do anything useful: it collects entry points but they're never
used anywhere.

This commit removes transform/CEP and add a comment about the dead code
in jvm/CEP which we need to enable and test.

Author: smarter

compiler/src/dotty/tools/backend/jvm/CollectEntryPoints.scala

@@ -16,9 +16,7 @@ import dotty.tools.dotc.util.SourcePosition
 import Decorators._
 import StdNames.nme
 
-/**
- * Created by dark on 26/11/14.
- */
+// FIXME: This is dead code, enable the phase and add tests for it.
 class CollectEntryPoints extends MiniPhase {
   def phaseName: String = "Collect entry points"
 

compiler/src/dotty/tools/dotc/Compiler.scala

@@ -118,7 +118,8 @@ class Compiler {
          new RestoreScopes,          // Repair scopes rendered invalid by moving definitions in prior phases of the group
          new SelectStatic,           // get rid of selects that would be compiled into GetStatic
          new sjs.JUnitBootstrappers, // Generate JUnit-specific bootstrapper classes for Scala.js (not enabled by default)
-         new CollectEntryPoints,     // Find classes with main methods
+         // FIXME: See comment in CollectEntryPoints
+         // new CollectEntryPoints,     // Find classes with main methods
          new CollectSuperCalls) ::   // Find classes that are called with super
     Nil