Moved trainblockers.py and boardmetrics.py into the ddd package
proper and made them importable for reuse outside the package.

Set up packaging so that we can publish the package to pypi.

Change-Id: I4001da1206c466d1575232601b57090fa77b5a1e

More or less complete usage example:

```py
        def process_transactions(transactions):
            mapper = PropertyMatcher()

            @mapper("transactionType=core:edge", "meta.edge:type=41")
            def edge(t):
                ''' match project edge transactions '''
                oldValue = [PHIDRef(p) for p in t["oldValue"]]
                newValue = [PHIDRef(p) for p in t["newValue"]]
                return [["projects", '', oldValue, newValue]]

            for taskid, t in transactions.result.items():
                st = sorted(t, key=itemgetter("dateCreated"))
                for record in st:
                    for row in mapper.run(record):
                        if row:
                            yield row

        transactions = get_some_transactions()

        for row in process_transactions(transactions):
            ''' do something with row '''
```

Change-Id: I6eac22574b02df75b9fd8c38d1a29856dd05f130

Sample output:

```
1.36.0-wmf.1   added         1
               comment       4
               resolved      1
1.36.0-wmf.10  added         6
               comment      11
               removed       2
               resolved      3
1.36.0-wmf.11  added         8
               comment      29
               invalid       1
               removed       4
               resolved      3
               stalled       1
1.36.0-wmf.12  added         2
               comment       4
               removed       1
               resolved      1
1.36.0-wmf.13  added         5
               comment      11
               removed       3
               resolved      4
1.36.0-wmf.14  added         5
               comment      11
               removed       4
               resolved      1
1.36.0-wmf.15  comment       3
1.36.0-wmf.16  added         9
               comment      15
               open          2
               removed       5
               resolved      5
1.36.0-wmf.17  comment       2
1.36.0-wmf.18  added         1
               comment      24
               removed       1
1.36.0-wmf.19  comment       3
1.36.0-wmf.2   added         7
               comment      27
               removed       7
               resolved      1
1.36.0-wmf.20  added         6
               comment      21
               declined      1
               removed       3
               resolved      3
1.36.0-wmf.21  added         2
               comment      12
               resolved      3
1.36.0-wmf.22  added         1
               comment       4
               removed       1
1.36.0-wmf.23  comment       3
1.36.0-wmf.24  comment       3
1.36.0-wmf.25  added         4
               comment      27
               removed       2
               resolved      4
1.36.0-wmf.26  added         4
               comment       4
               open          1
               resolved      6
1.36.0-wmf.27  added         5
               comment      12
               removed       2
               resolved      3
1.36.0-wmf.28  added         6
               comment      16
               removed       7
               resolved      2
1.36.0-wmf.29  added         5
               comment       8
               removed       4
               resolved      4
1.36.0-wmf.3   added         5
               comment      12
               removed       4
               resolved      1
1.36.0-wmf.30  added         5
               comment      13
               removed       1
               resolved      4
1.36.0-wmf.31  added         4
               comment       8
               removed       2
               resolved      2
1.36.0-wmf.32  added         2
               comment      17
               removed       2
1.36.0-wmf.33  added         2
               comment      15
               removed       2
1.36.0-wmf.34  added         6
               comment      19
               open          2
               removed       4
               resolved      4
1.36.0-wmf.35  added         7
               comment      10
               open          1
               removed       4
               resolved      5
1.36.0-wmf.36  added         9
               comment      33
               declined      1
               open          1
               removed       2
               resolved      7
1.36.0-wmf.37  added         9
               comment      39
               removed       8
               resolved      1
1.36.0-wmf.38  added         3
               comment       8
               removed       3
1.36.0-wmf.39  added         1
               resolved      1
1.36.0-wmf.4   added         3
               comment      11
               removed       2
               resolved      1
1.36.0-wmf.40  comment       1
1.36.0-wmf.5   comment      19
1.36.0-wmf.6   comment       5
1.36.0-wmf.7   added         1
               comment       1
               removed       1
1.36.0-wmf.8   added         2
               comment       7
               removed       1
               resolved      1
1.36.0-wmf.9   added         4
               comment      25
               open          2
               removed       2
               resolved      3
               stalled       1
1.37.0-wmf.1   added         2
```

Change-Id: Iadf025ef26e017376dcdc8aefff4a0e50651c34d