Add direct hyperlinks to Specification (#112)

Also adds Jamo to specification, from #111

docs/specs.rst

@@ -12,31 +12,35 @@ Width of -1
 
 The following have a column width of -1 for function :func:`wcwidth.wcwidth`
 
-- C0 control characters (U+001 through U+01F).
-- C1 control characters and DEL (U+07F through U+0A0).
+- ``C0`` control characters (`U+0001`_` through `U+001F`_).
+- ``C1`` control characters and ``DEL`` (`U+007F`_ through `U+00A0`_).
 
-If any character in sequence contains C0 or C1 control characters, the final
+If any character in sequence contains ``C0`` or ``C1`` control characters, the final
 return value of of :func:`wcwidth.wcswidth` is -1.
 
 Width of 0
 ----------
 
-Any characters defined by category codes in DerivedGeneralCategory txt files:
+Any characters defined by category codes in `DerivedGeneralCategory.txt`_ files:
 
 - 'Me': Enclosing Combining Mark, aprox. 13 characters.
 - 'Mn': Nonspacing Combining Mark, aprox. 1,839 characters.
 - 'Mc': Spacing Mark, aprox. 443 characters.
 - 'Cf': Format control character, aprox. 161 characters.
-- 'Zl': U+2028 LINE SEPARATOR only
-- 'Zp': U+2029 PARAGRAPH SEPARATOR only
+- 'Zl': `U+2028`_ LINE SEPARATOR only
+- 'Zp': `U+2029`_ PARAGRAPH SEPARATOR only
 - 'Sk': Modifier Symbol, aprox. 4 characters of only those where phrase
   ``'EMOJI MODIFIER'`` is present in comment of unicode data file.
 
-The NULL character (``U+0000``).
+The NULL character (`U+0000`_).
 
-Any character following a ZWJ (``U+200D``) when in sequence by
+Any character following ZWJ (`U+200D`_) when in sequence by
 function :func:`wcwidth.wcswidth`.
 
+Hangul Jamo Jungseong and "Extended-B" code blocks, `U+1160`_ through
+`U+11FF`_ and `U+D7B0`_ through `U+D7FF`_.
+
+
 Width of 1
 ----------
 
@@ -47,12 +51,29 @@ Width of 2
 ----------
 
 Any character defined by East Asian Fullwidth (``F``) or Wide (``W``)
-properties in EastAsianWidth txt files, except those that are defined by the
+properties in `EastAsianWidth.txt`_ files, except those that are defined by the
 Category codes of Nonspacing Mark (``Mn``) and Spacing Mark (``Mc``).
 
 Any characters of Modifier Symbol category, ``'Sk'`` where ``'FULLWIDTH'`` is
 present in comment of unicode data file, aprox. 3 characters.
 
-Any character in sequence with U+FE0F (Variation Selector 16) defined by
-Emoji Variation Sequences txt as ``emoji style``.
-
+Any character in sequence with `U+FE0F`_ (Variation Selector 16) defined by
+`emoji-variation-sequences.txt`_ as ``emoji style``.
+
+
+.. _`U+0000`: https://codepoints.net/U+0000
+.. _`U+0001`: https://codepoints.net/U+0001
+.. _`U+001F`: https://codepoints.net/U+001F
+.. _`U+007F`: https://codepoints.net/U+007F
+.. _`U+00A0`: https://codepoints.net/U+00A0
+.. _`U+1160`: https://codepoints.net/U+1160
+.. _`U+11FF`: https://codepoints.net/U+11FF
+.. _`U+200D`: https://codepoints.net/U+200D
+.. _`U+2028`: https://codepoints.net/U+2028
+.. _`U+2029`: https://codepoints.net/U+2029
+.. _`U+D7B0`: https://codepoints.net/U+D7B0
+.. _`U+D7FF`: https://codepoints.net/U+D7FF
+.. _`U+FE0F`: https://codepoints.net/U+FE0F
+.. _`DerivedGeneralCategory.txt`: https://www.unicode.org/Public/UCD/latest/ucd/extracted/DerivedGeneralCategory.txt
+.. _`EastAsianWidth.txt`: https://www.unicode.org/Public/UCD/latest/ucd/EastAsianWidth.txt`
+.. _`emoji-variation-sequences.txt`: https://www.unicode.org/Public/UCD/latest/ucd/emoji/emoji-variation-sequences.txt