We got funny interactions since PR #1656:

- the last `debug_info`-related option seen in a list of options after
  profile merge is kept, allowing later profiles from overtaking earlier
  ones
- if you go `rebar3 as a,b,c compile`, the options from profile A come
  before B, which come before C, so C's options win
- overrides are applied in order of profile as well, giving a priority
  to a later profile than an earlier one
- The values in overrides are prepended rather than suffixed to the
  existing list
- this means if we have to overrides adding options, such as `default`
  adding `no_debug_info', and `dialyze` adding `debug_info`, the
  results are `[debug_info]` as `dialyze` is applied first, and then
  `[no_debug_info, debug_info]` as `default` overrides are applied
- the final result is `no_debug_info` always winning when erl_opts are
  overriden specifically.

only `debug_info` options are going to suffer this, and in the context of
overrides. Other `erl_opts` should be fine. I'm not sure how that can be
fixed at all.

In the meanwhile, we can add support back while leaving the default to
not having debug information. This is done by:

- moving all `no_debug_info` options to the `prod` profile
- forcing `prod` to be called by `./bootstrap` so that most people keep
  getting no debug info
- anyone calling `rebar3 clean -a`  and then rebuilding with `rebar3
  escriptize` (i.e. rebar3 devs) get debug info going

This is up for review and discussion.

Fixes some lager warnings since config changes

The path reloading of plugins had been fixed properly, but the problem
is that the paths it was using to re-load only considered the current
compile step, rather than the overall state of plugins. As such, the
reloaded paths after plugin compilation only reloaded the *latest*
plugin and not the other ones.

This fix forces the addition of all built plugin paths to the code paths
after a plugin compile job is run. This ensures that the path is clean
for initial plugin deps (only add those that are required), and is
re-made total after the fact (add all the plugins possible).

This commit also includes a system tests suite that can be run
optionally; the problem with this plugin mechanism was impossible to
find through mocked dependencies, and a working counterexample was
provided to us. The systest suite can be run against real projects
without conflict to make sure no regressions are hit.

Eliminates a lager warning due to config format deprecation

This replaces all deprecated function usage by alternative ones based on
a version switch enacted at compile time, preventing all warnings.

This will likely introduce some possible runtime errors in using a
Rebar3 compiled on OTP-20 or OTP-21 back in versions 19 and earlier, but
we can't really work around that.

A bunch of dependencies have been updated to support OTP-21 without
warnings as well.

Get more up-to-date root certs. This was blocked for a while because
certifi wouldn't build on windows, but this is now fixed, with minimal
changes to the use case -- only a small change in the bootstrap script
is required.

The new certifi lib is also a few megabytes lighter than before, which
is good for rebar3.

This fixes the output of end_per_testcase crash notifications when the
test passes.

This also detect an issue of the kind with rebar_pkg_SUITE which is now
fixed.

Fixes an issue where some skipped test suites could end up misreported
as the previous suite. See
https://github.com/ferd/cth_readable/issues/10

This also patches up a problem for hooks when dealing with directories
with spaces in them, and reduces complexity of bootstrap file.

relx ~> 3.22.0
erlware_commons ~> 0.22.0
cf ~> 0.2.2

Repeats some of the steps used in the bootstrap script for non-windows
systems so that 'rebar3 escriptize' can be used in development for
faster results:

- ./bootstrap  9.95s user 1.55s system 102% cpu 11.234 total
- rebar3 escriptize  0.49s user 0.14s system 101% cpu 0.623 total

Prior to this patch, the escriptize command flat out selected all
declared dependencies.

This patch instead looks at the app files and only includes the
dependencies of the top level app and the extra ones, avoiding to
package more apps than required.

This required a version bump on cth_readable as it mistakenly included
'syntax_lib' instead of 'syntax_tools' as a dependency.

latest mozilla bundles

The new version fixes parse transforms over OTP incompatibility that
would crash entire compile runs before.

this is slower than the compile time check but i guess packaging rebars with
repos is still a thing and i think only the eunit and ct providers call it
anyways