Remove reliance on django-markdownx (#3231)

* Remove reliance on django-markdownx

- We are now rendering notes on the client side using easymde
- No longer any need to utilize the markdownx integration
- Adds character limit for notes fields`

* Adjust legacy migrations - remove references to markdownx

* Fix bug for company notes field

InvenTree/stock/migrations/0018_auto_20200202_0103.py

@@ -1,7 +1,6 @@
 # Generated by Django 2.2.9 on 2020-02-02 01:03
 
-from django.db import migrations
-import markdownx.models
+from django.db import migrations, models
 
 
 class Migration(migrations.Migration):
@@ -14,6 +13,6 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='stockitem',
             name='notes',
-            field=markdownx.models.MarkdownxField(blank=True, help_text='Stock Item Notes'),
+            field=models.TextField(blank=True, help_text='Stock Item Notes'),
         ),
     ]

InvenTree/stock/migrations/0020_auto_20200206_1213.py

@@ -1,7 +1,6 @@
 # Generated by Django 2.2.9 on 2020-02-06 12:13
 
-from django.db import migrations
-import markdownx.models
+from django.db import migrations, models
 
 
 class Migration(migrations.Migration):
@@ -14,6 +13,6 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='stockitem',
             name='notes',
-            field=markdownx.models.MarkdownxField(blank=True, help_text='Stock Item Notes', null=True),
+            field=models.TextField(blank=True, help_text='Stock Item Notes', null=True),
         ),
     ]

InvenTree/stock/migrations/0034_auto_20200426_0602.py

@@ -4,7 +4,6 @@ import InvenTree.fields
 import django.core.validators
 from django.db import migrations, models
 import django.db.models.deletion
-import markdownx.models
 import mptt.fields
 
 
@@ -56,7 +55,7 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='stockitem',
             name='notes',
-            field=markdownx.models.MarkdownxField(blank=True, help_text='Stock Item Notes', null=True, verbose_name='Notes'),
+            field=models.TextField(blank=True, help_text='Stock Item Notes', null=True, verbose_name='Notes'),
         ),
         migrations.AlterField(
             model_name='stockitem',

InvenTree/stock/migrations/0077_alter_stockitem_notes.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.2.13 on 2022-06-20 07:28
+
+import InvenTree.fields
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0076_alter_stockitem_status'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='stockitem',
+            name='notes',
+            field=InvenTree.fields.InvenTreeNotesField(blank=True, help_text='Stock Item Notes', max_length=50000, null=True, verbose_name='Notes'),
+        ),
+    ]

InvenTree/stock/models.py

@@ -18,7 +18,6 @@ from django.urls import reverse
 from django.utils.translation import gettext_lazy as _
 
 from jinja2 import Template
-from markdownx.models import MarkdownxField
 from mptt.managers import TreeManager
 from mptt.models import MPTTModel, TreeForeignKey
 
@@ -29,7 +28,8 @@ import InvenTree.tasks
 import label.models
 import report.models
 from company import models as CompanyModels
-from InvenTree.fields import InvenTreeModelMoneyField, InvenTreeURLField
+from InvenTree.fields import (InvenTreeModelMoneyField, InvenTreeNotesField,
+                              InvenTreeURLField)
 from InvenTree.models import InvenTreeAttachment, InvenTreeTree
 from InvenTree.serializers import extract_int
 from InvenTree.status_codes import StockHistoryCode, StockStatus
@@ -708,11 +708,7 @@ class StockItem(MetadataMixin, MPTTModel):
         choices=StockStatus.items(),
         validators=[MinValueValidator(0)])
 
-    notes = MarkdownxField(
-        blank=True, null=True,
-        verbose_name=_("Notes"),
-        help_text=_('Stock Item Notes')
-    )
+    notes = InvenTreeNotesField(help_text=_('Stock Item Notes'))
 
     purchase_price = InvenTreeModelMoneyField(
         max_digits=19,