lint: Use zulint's methods for lister and printing errors.

Remove lister, printer and README files from server_lib.

Author: amanagr

tools/custom_check.py

@@ -137,7 +137,6 @@
 
 markdown_docs_length_exclude = {
     "zulip_bots/zulip_bots/bots/converter/doc.md",
-    "tools/server_lib/README.md",
 }
 
 markdown_rules = RuleList(

tools/pep8.py

@@ -7,7 +7,7 @@
 import subprocess
 import sys
 
-from server_lib.printer import print_err, colors
+from zulint.printer import print_err, colors
 
 from typing import List
 

tools/run-mypy

@@ -10,7 +10,7 @@ import subprocess
 
 from collections import OrderedDict
 from pathlib import PurePath
-from server_lib import lister
+from zulint import lister
 from typing import cast, Dict, List
 
 TOOLS_DIR = os.path.dirname(os.path.abspath(__file__))