set the dep as the project app before running hooks

don't duplicate hooks for top level app

ignore optional deps for now

add to end of code path not the beginning in handle_deps

Add support for an unlock command

Allows to remove entries from the lock file, or the lock file as a
whole.

Default deps always to the default profile

Mainly CT changes

When fetching dependencies for the first time using a profile (`rebar3
as prod release` or `rebar3 ct`), the dependencies get fetched into the
non-default profile. This has two consequences:

- the files get re-downloaded on follow-up runs
- the lock file includes incomplete or too many deps in its list

This patch forces dependencies in the default profile to be stored in
_build/default/lib even when running under other profiles, then symlinks
them to the correct one.

This makes it so common dependencies in 'default' be downloaded there
and avoids re-downloading them. Should also fix the lock issues.

include applications list in compile sort

Rename wtf->report, add all dep versions

Improve error handling in ct provider

support single atoms for pkg deps, fetch highest version available

Warn on bad use of include_lib but try to find the header anyway

disallow suites in project root

fixes #331

rm old beams, make erlcinfo graph per app isntad of global to project

merge rebar2's Refactor logic and optimizations in rebar_erlc_compiler:doterl_compile/4 #467

fix build instruction