refactor main to for ease of integration (#1948)

* main: split main into a bunch of "main routines"

[wip] since there are a few references to BinExport2
that are in progress elsewhre. Next commit will remove them.

* main: remove references to wip BinExport2 code

* changelog

* main: rename first position argument "input_file"

closes #1946

* main: linters

* main: move rule-related routines to capa.rules

ref #1821

* main: extract routines to capa.loader module

closes #1821

* add loader module

* loader: learn to load freeze format

* freeze: use new cli arg handling

* Update capa/loader.py

Co-authored-by: Moritz <mr-tz@users.noreply.github.com>

* main: remove duplicate documentation

* main: add doc about where some functions live

* scripts: migrate to new main wrapper helper functions

* scripts: port to main routines

* main: better handle auto-detection of backend

* scripts: migrate bulk-process to main wrappers

* scripts: migrate scripts to main wrappers

* main: rename *_from_args to *_from_cli

* changelog

* cache-ruleset: remove duplication

* main: fix tag handling

* cache-ruleset: fix cli args

* cache-ruleset: fix special rule cli handling

* scripts: fix type bytes

* main: remove old TODO message

* loader: fix references to binja extractor

---------

Co-authored-by: Moritz <mr-tz@users.noreply.github.com>

scripts/detect_duplicate_features.py

@@ -48,7 +48,7 @@ def find_overlapping_rules(new_rule_path, rules_path):
     overlapping_rules = []
 
     # capa.rules.RuleSet stores all rules in given paths
-    ruleset = capa.main.get_rules(rules_path)
+    ruleset = capa.rules.get_rules(rules_path)
 
     for rule_name, rule in ruleset.rules.items():
         rule_features = rule.extract_all_features()