Properly capitalise UTF-8/ASCII in the documentation

docs/abi-spec.rst

@@ -199,9 +199,9 @@ on the type of ``X`` being
 
 - ``string``:
 
-  ``enc(X) = enc(enc_utf8(X))``, i.e. ``X`` is utf-8 encoded and this value is interpreted
+  ``enc(X) = enc(enc_utf8(X))``, i.e. ``X`` is UTF-8 encoded and this value is interpreted
   as of ``bytes`` type and encoded further. Note that the length used in this subsequent
-  encoding is the number of bytes of the utf-8 encoded string, not its number of characters.
+  encoding is the number of bytes of the UTF-8 encoded string, not its number of characters.
 
 - ``uint<M>``: ``enc(X)`` is the big-endian encoding of ``X``, padded on the higher-order
   (left) side with zero-bytes such that the length is 32 bytes.

docs/layout-of-source-files.rst

@@ -330,8 +330,8 @@ Single-line comments (``//``) and multi-line comments (``/*...*/``) are possible
 
 .. note::
   A single-line comment is terminated by any unicode line terminator
-  (LF, VF, FF, CR, NEL, LS or PS) in utf8 encoding. The terminator is still part of
-  the source code after the comment, so if it is not an ascii symbol
+  (LF, VF, FF, CR, NEL, LS or PS) in UTF-8 encoding. The terminator is still part of
+  the source code after the comment, so if it is not an ASCII symbol
   (these are NEL, LS and PS), it will lead to a parser error.
 
 Additionally, there is another type of comment called a natspec comment,

docs/yul.rst

@@ -688,7 +688,7 @@ We will use a destructuring notation for the AST nodes.
         Let G'', L'', mode = E(Gn, L', block)
         G'', Ln, L''[$ret1], ..., L''[$retm]
     E(G, L, l: StringLiteral) = G, L, utf8EncodeLeftAligned(l),
-        where utf8EncodeLeftAligned performs a utf8 encoding of l
+        where utf8EncodeLeftAligned performs a UTF-8 encoding of l
         and aligns it left into 32 bytes
     E(G, L, n: HexNumber) = G, L, hex(n)
         where hex is the hexadecimal decoding function