Fix some broken links in documentation

Author: Jentsch

docs/docs/reference/changed-features/eta-expansion.md

@@ -35,7 +35,7 @@ rather than `next _`.
 The reason for excluding nullary methods from automatic eta expansion
 is that Scala implicitly inserts the `()` argument, which would
 conflict with eta expansion. Automatic `()` insertion is
-[limited](../dropped/auto-apply.md) in Dotty, but the fundamental ambiguity
+[limited](../dropped-features/auto-apply.md) in Dotty, but the fundamental ambiguity
 remains.
 
 [More details](eta-expansion-spec.html)

docs/docs/reference/dropped-features/early-initializers.md

@@ -8,4 +8,4 @@ Early initializers of the form
  class C extends { ... } with SuperClass ...
 
 have been dropped. They were rarely used, and mostly to compensate for the lack of
-[trait parameters](../trait-parameters.md), which are now directly supported in Dotty.
+[trait parameters](../other-new-features/trait-parameters.md), which are now directly supported in Dotty.

docs/docs/reference/other-new-features/inline.md

@@ -3,7 +3,7 @@ layout: doc-page
 title: Inline
 ---
 
-`inline` is a new [soft modifier](./soft-modifier.html) that guarantees that a definition will be inline at the point of use. Example:
+`inline` is a new [soft modifier](../soft-modifier.html) that guarantees that a definition will be inline at the point of use. Example:
 
  object Config {
   inline val logging = false

docs/docs/reference/other-new-features/principled-meta-programming.md

@@ -624,7 +624,7 @@ and adding quoted variants `'(...)`, `'{...}` and `'[...]` to the
   | ‘'’ ‘[’ Type ‘]’
 
 Syntax changes are given relative to the [Dotty reference
-grammar](../internal/syntax.md).
+grammar](../../internals/syntax.md).
 
 An alternative syntax would treat `'` as a separate operator. This
 would be attractive since it enables quoting single identifiers as
@@ -764,7 +764,7 @@ environments and terms.
   Es |- 't: expr T
 
 The meta theory of a slightly simplified variant 2-stage variant of this calculus
-is studied [separately](simple-smp.md).
+is studied [separately](../simple-smp.md).
 
 ## Going Further