handle missing package in registry by skipping

Fix dupes in deps provider, support atom pkgs

Kovyl2404 app discover profile duplication

include relx templates in escript

Whenever files were being locked *and* provided in rebar.config
duplicates could be printed. This is taken care of.

Also whenever atom packages were being used, they would cause the merge
step to fail. The new format does proper name-based deduplication of
resources, giving priority to locks to work.

ModificatioN/needs-update support is still in.

This may also act as a fix for #341, if automation isn't required too
much.

on upgrade of git branch check against remote

upgrade relx dep to latest mustache branch commit

Remove erlydtl and replace with mustache

enable parse transformations in rebar config

Conflicts:
	test/rebar_profiles_SUITE.erl

don't load package registry unless there are pkg deps to solve

include _checkouts in release lib dirs if it exists

read in application details into app_info after fetch

Avoid topsorting deps twice

They can be culled and reused in one sort pass.

support templates even when not run as escript

handle transitive deps being promoted

merge_locks crashed if a config didn't have a deps entry

remove warning if header not found, could be in a macro

Support 18.0+

fix template listing (re-add escript_incl_extra)

Fixes regression from 3a63bec39f (diff-31d7a50c99c265ca2793c20961b60979L4)
which meant listing templates doesn't work (rebar3 new help)

real bootstrapping