Start implementing error explanations

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diff --git a/src/errors/FieldCollision.txt b/src/errors/FieldCollision.txt
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+Explanation: You can combine records if they don't share any fields in common,
+like this:
+
+
+    ┌───────────────────────────────────────────┐
+    │ { foo = 1, bar = "ABC" } ∧ { baz = True } │
+    └───────────────────────────────────────────┘
+
+
+    ┌────────────────────────────────────────┐
+    │ λ(r : { baz : Bool}) → { foo = 1 } ∧ r │
+    └────────────────────────────────────────┘
+
+
+... but you cannot merge two records that share the same field
+
+For example, the following expression is $_NOT valid:
+
+
+    ┌───────────────────────────────────────────┐
+    │ { foo = 1, bar = "ABC" } ∧ { foo = True } │  Invalid: Colliding ❰foo❱ fields
+    └───────────────────────────────────────────┘
+
+
+You combined two records that share the following field:
+
+↳ $txt0
+
+... which is not allowed
+
+Some common reasons why you might get this error:
+
+● You tried to use ❰∧❱ to update a field's value, like this:
+
+
+    ┌────────────────────────────────────────┐
+    │ { foo = 1, bar = "ABC" } ∧ { foo = 2 } │
+    └────────────────────────────────────────┘
+                                   ⇧
+                                   Invalid attempt to update ❰foo❱'s value to ❰2❱
+
+  Field updates are intentionally not allowed as the Dhall language discourages
+  patch-oriented programming