Remove Enum.equal?

There is a branch work refactoring Enum and Enum.equal?
contains some limitations. We are removing it for now
since it was not officially released yet.
IEx.Remsh should be private
Deprecate Exception.format_entry in favor of Exception.format_stacktrace_entry
Fix h(c/2), closes #1101
Add IEx processing to Kernel.CLI
Release v0.8.3
Start v0.9.0.dev work
Add initial support for .iex files
Use System.halt instead of :erlang.halt
Don't wrap Code.require_file
Include description of .iex in the doc for IEx
Expand ~/.iex before using it
Pass the stacktrace explicitly to IEx.Util functions
Don't mention the f() helper for now (it's not supported yet)
Move load_dot_iex to IEx.Server, after `require IEx.Helpers`
Fix a bug in ~/.iex expansion
Split the long :elixir.eval line into shorter ones
Add missing comma in the doc
Add :elixir.scope_for_eval/2 convenience function
Add import_file/1 and /2 helpers