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

cth_readable 1.2.0 uses cf 0.2.1 to output colors, which makes it
support dumb terminals without issue.

This fixes a typo that could cause failure in some test runs.