Remove repetition in definition of var(u)int types

BinaryEncoding.md

@@ -31,42 +31,39 @@ for a proposal for layer 1 structural compression.
 
 # Data types
 
-### uint8
-A single-byte unsigned integer.
+### `uintN`
+An unsigned integer of _N_ bits,
+represented in _N_/8 bytes in [little endian](https://en.wikipedia.org/wiki/Endianness#Little-endian) order.
+_N_ is either 8, 16, or 32.
 
-### uint32
-A four-byte little endian unsigned integer.
+### `varuintN`
+A [LEB128](https://en.wikipedia.org/wiki/LEB128) variable-length integer, limited to _N_ bits (i.e., the values [0, 2^_N_-1]),
+represented by _at most_ ceil(_N_/7) bytes that may contain padding `0x80` bytes.
 
-### varint32
-A [Signed LEB128](https://en.wikipedia.org/wiki/LEB128#Signed_LEB128) variable-length integer, limited to int32 values. `varint32` values may contain leading zero or one bits and must be at most 5 bytes.
+Note: Currently, the only sizes used are `varuint1`, `varuint7`, and `varuint32`,
+where the former two are used for compatibility with potential future extensions.
 
-### varuint1
-A [LEB128](https://en.wikipedia.org/wiki/LEB128) variable-length integer, limited to the values 0 or 1. `varuint1` values must be exactly one byte. (This type is mainly used for compatibility with potential future extensions.)
+### `varintN`
+A [Signed LEB128](https://en.wikipedia.org/wiki/LEB128#Signed_LEB128) variable-length integer, limited to _N_ bits (i.e., the values [-2^(_N_-1), +2^(_N_-1)-1]),
+represented by _at most_ ceil(_N_/7) bytes that may contain padding `0x80` or `0xFF` bytes.
 
-### varuint7
-A [LEB128](https://en.wikipedia.org/wiki/LEB128) variable-length integer, limited to the values [0, 127]. `varuint7` values must be exactly one byte. (This type is mainly used for compatibility with potential future extensions.)
+Note: Currently, the only sizes used are `varuint32` and `varuint64`.
 
-### varuint32
-A [LEB128](https://en.wikipedia.org/wiki/LEB128) variable-length integer, limited to uint32 values. `varuint32` values may contain leading zeros and must be at most 5 bytes.
-
-### varint64
-A [Signed LEB128](https://en.wikipedia.org/wiki/LEB128#Signed_LEB128) variable-length integer, limited to int64 values. `varint64` values may contain leading zero or one bits and must be at most 10 bytes.
-
-### value_type
+### `value_type`
 A single-byte unsigned integer indicating a [value type](AstSemantics.md#types). These types are encoded as:
 * `1` indicating type `i32` 
 * `2` indicating type `i64` 
 * `3` indicating type `f32` 
 * `4` indicating type `f64`
 
-### external_kind
+### `external_kind`
 A single-byte unsigned integer indicating the kind of definition being imported or defined:
 * `0` indicating a `Function` [import](Modules.md#imports) or [definition](Modules.md#function-and-code-sections)
 * `1` indicating a `Table` [import](Modules.md#imports) or [definition](Modules.md#table-section)
 * `2` indicating a `Memory` [import](Modules.md#imports) or [definition](Modules.md#linear-memory-section)
 * `3` indicating a `Global` [import](Modules.md#imports) or [definition](Modules.md#global-section)
 
-### resizable_limits
+### `resizable_limits`
 A packed tuple that describes the limits of a
 [table](AstSemantics.md#table) or [memory](AstSemantics.md#resizing):
 
@@ -79,7 +76,7 @@ A packed tuple that describes the limits of a
 The "flags" field may later be extended to include a flag for sharing (between
 threads).
 
-### init_expr
+### `init_expr`
 The encoding of an [initializer expression](Modules.md#initializer-expression)
 is the normal encoding of the expression followed by the `end` opcode as a
 delimiter.