Fix mistakes in docs

docs/tut/crash-course/12-actions.md

@@ -26,9 +26,9 @@ local source = vide.source
 local effect = vide.effect
 local cleanup = vide.cleanup
 
-local function changed(prop: string, callback: (new) -> ())
+local function changed(property: string, callback: (new) -> ())
     return action(function(instance)
-        local connection = instance:GetPropertyChangedSignal(prop):Connect(function()
+        local connection = instance:GetPropertyChangedSignal(property):Connect(function()
             callback(instance[property])
         end)
 

docs/tut/crash-course/14-concepts.md

@@ -69,7 +69,7 @@ local count = source(0)
 
 root(function()
     local text = derive(function()
-        return "count: " .. text()
+        return "count: " .. count()
     end)
 
     effect(function()

docs/tut/crash-course/5-effect.md

@@ -53,7 +53,7 @@ effects depending on it.
 
 You can also read from a source within an effect without the effect tracking it.
 
-```lua
+```luau
 local source = vide.source
 local effect = vide.effect
 local untrack = vide.untrack

docs/tut/crash-course/6-scope.md

@@ -35,8 +35,6 @@ local function setup()
     effect(function()
         print(count())
     end)
-
-    return count
 end
 
 setup() -- error, effect() tried to create a reactive scope with no stable scope

docs/tut/crash-course/7-reactive-component.md

@@ -34,14 +34,10 @@ count source is created inside the component.
 External sources can also be passed into components for them to use.
 
 ```luau
-local function Counter(props: { count: () -> number })
+local function CountDisplay(props: { count: () -> number })
     local count = props.count
 
-    local instance = create "TextButton" {
-        Activated = function()
-            count(count() + 1)
-        end
-    }
+    local instance = create "TextLabel" {}
 
     effect(function()
         instance.Text = "count: " .. count()
@@ -52,11 +48,11 @@ end
 
 local count = source(0)
 
-Counter {
+CountDisplay {
     count = count
 }
 
-count(1) -- the Counter component will update to display this count
+count(1) -- the CountDisplay component will update to display this count
 ```
 
 Sources can be created internally or passed in from externally, there are no