Clean up help screen, get rid of util.py (#1027)

* More refactoring of cli.py

break up code from cli.py (now in jrnl.py) up into smaller functions
get rid of export mode
move --encrypt and --decrypt to commands.py
clean up the help screen even more
update flag name for import

* reorganize code, move around lots of functions

* clean up import statements

* move run function out of cli and into jrnl

* rename confusingly named function

* move editor function into editor file

* rename parse_args.py to args.py to make room for more args functions

* Fix error in test suite for windows

I accidentally flipped the conditional, so this fixes it.

Co-authored-by: Micah Jerome Ellison <micah.jerome.ellison@gmail.com>

* Update app description on help screen

Co-authored-by: Micah Jerome Ellison <micah.jerome.ellison@gmail.com>

jrnl/editor.py

@@ -0,0 +1,57 @@
+import logging
+import os
+import shlex
+import subprocess
+import sys
+import tempfile
+import textwrap
+
+from .color import ERROR_COLOR
+from .color import RESET_COLOR
+from .os_compat import on_windows
+
+
+def get_text_from_editor(config, template=""):
+    filehandle, tmpfile = tempfile.mkstemp(prefix="jrnl", text=True, suffix=".txt")
+    os.close(filehandle)
+
+    with open(tmpfile, "w", encoding="utf-8") as f:
+        if template:
+            f.write(template)
+
+    try:
+        subprocess.call(shlex.split(config["editor"], posix=on_windows) + [tmpfile])
+    except Exception as e:
+        error_msg = f"""
+        {ERROR_COLOR}{str(e)}{RESET_COLOR}
+
+        Please check the 'editor' key in your config file for errors:
+            {repr(config['editor'])}
+        """
+        print(textwrap.dedent(error_msg).strip(), file=sys.stderr)
+        exit(1)
+
+    with open(tmpfile, "r", encoding="utf-8") as f:
+        raw = f.read()
+    os.remove(tmpfile)
+
+    if not raw:
+        print("[Nothing saved to file]", file=sys.stderr)
+
+    return raw
+
+
+def get_text_from_stdin():
+    _how_to_quit = "Ctrl+z and then Enter" if on_windows else "Ctrl+d"
+    print(
+        f"[Writing Entry; on a blank line, press {_how_to_quit} to finish writing]\n",
+        file=sys.stderr,
+    )
+    try:
+        raw = sys.stdin.read()
+    except KeyboardInterrupt:
+        logging.error("Write mode: keyboard interrupt")
+        print("[Entry NOT saved to journal]", file=sys.stderr)
+        sys.exit(0)
+
+    return raw