Added documentation for LTT and LBTT and fixed some errors (#777)

* Update LBTT rate increase for non-primary residences

* Fix SDLT description

* Add documention for LTT and LBTT

* Change the legend in graphs

changelog_entry.yaml

@@ -0,0 +1,8 @@
+- bump: patch
+  changes:
+    added:
+    - Documentation for Land and Buildings Transaction Tax.
+    - Documentation for Land Transaction Tax.
+    fixed:
+    - Updated LBTT rate increase for non-primary residences.
+    - Fixed SDLT description.

docs/book/_toc.yml

@@ -17,6 +17,8 @@ parts:
       - file: programs/contrib/ubi-center/carbon-tax
       - file: programs/gov/ofgem/energy-price-guarantee
       - file: programs/gov/dcms/bbc/tv-licence
+      - file: programs/gov/revenue_scotland/land-and-buildings-transaction-tax
+      - file: programs/gov/wra/land-transaction-tax
   - caption: Using the model
     chapters:
       - file: usage/getting-started

docs/book/programs/gov/hmrc/stamp-duty.ipynb

@@ -7,7 +7,7 @@
    "source": [
     "# Stamp Duty Land Tax\n",
     "\n",
-    "Stamp Duty Land Tax (SDLT) is a tax imposed on the purchase and rental of properties or land with values over a certain threshold in the UK. It applies to both residential and non-residential (commercial) properties. \n",
+    "Stamp Duty Land Tax (SDLT) is a tax imposed on the purchase and rental of properties or land with values over a certain threshold in England and Northern Ireland. It applies to both residential and non-residential (commercial) properties. \n",
     "\n",
     "Stamp Duty Land Tax parameters can be found in `policyengine_uk/parameters/gov/hmrc/stamp_duty` and logic in `policyengine_uk/variables/gov/hmrc/stamp_duty_land_tax.py`.\n",
     "\n",
@@ -7367,7 +7367,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.12"
+   "version": "3.9.7"
   },
   "orig_nbformat": 4
  },