v1.15.5

1. Enhancements

IEx

• [IEx.Autocomplete] Speed up loading of struct suggestions

2. Bug fixes

Elixir

• [Code.Fragment] Fix Code.Fragment.surround_context/2 for aliases and submodules of non-aliases
• [Kernel] Ensure stacktrace is included when necessary when rescuing multiple exceptions in the same branch
• [Kernel] Fix index in error message for unused optional arguments

ExUnit

• [ExUnit.Diff] Fix scenario where diff would not show up due to a timed-out loop

IEx

• [IEx] Force group leader to run as a binary and unicode in IEx

Mix

• [mix compile] Do not assume blake is always available
• [mix format] Load and compile plugins if specified in subdirectories