Forbid build metadata ordering (See #18)

SemVer 2.0.0 states that "Build metadata SHOULD be ignored when
determining version precedence".

This means that, when comparing ``0.1.0+1`` to ``0.1.0+bcd``::

    >>> Version('0.1.0+1') == Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') != Version('0.1.0+bcd')
    True
    >>> Version('0.1.0+1') < Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') > Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') <= Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') >= Version('0.1.0+bcd')
    False
    >>> compare(Version('0.1.0+1'), Version('0.1.0+bcd'))
    NotImplemented

This change also has the following effects:
- When including build metadata in a ``Spec``, the only valid options
  are ``Spec('==0.1.0+sth')`` and ``Spec('!=0.1.0+sth')``
- The meaning of ``Spec('==0.1.0+')`` is now "Only version 0.1.0 without
  build metadata"
- ``Spec('==0.1.0')`` now matches ``Version('0.1.0+anything')``

1 files changed, 30 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index fac48ca..cd7c3db 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,36 @@
 ChangeLog
 =========
 
+2.5.0 (master)
+--------------
+
+*Bugfix:*
+
+    `#18 <https://github.com/rbarrois/python-semanticversion/issues/18>`_: According to SemVer 2.0.0, build numbers aren't ordered.
+
+    * Remove specs of the ``Spec('<1.1.3+')`` form
+    * Comparing ``Version('0.1.0')`` to ``Version('0.1.0+bcd')`` has new
+      rules::
+
+          >>> Version('0.1.0+1') == Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') != Version('0.1.0+bcd')
+          True
+          >>> Version('0.1.0+1') < Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') > Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') <= Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') >= Version('0.1.0+bcd')
+          False
+          >>> compare(Version('0.1.0+1'), Version('0.1.0+bcd'))
+          NotImplemented
+
+    * :func:`semantic_version.compare` returns ``NotImplemented`` when its
+      parameters differ only by build metadata
+    * ``Spec('<=1.3.0')`` now matches ``Version('1.3.0+abde24fe883')``
+
 2.4.2 (2015-07-02)
 ------------------