add implicit casts to string when getting data from yaml as yaml tends to return numbers as numbers. fixes #23 I think
mysql_reader: set time_zone to UTC

Setting time_zone to UTC helps to avoid porblems
with duplicated timestamps for different records
in moments of switching to daylight saving time.
Foreign Data Wrapper support

Use of foreign data wrappers speeds up data importing a lot.
There may be some bugs and incompatibilities though.
For example, zero-timestamp ("0000-00-00 00:00:00") is invalid
in postgres, so must not be present in foreign table. If there are
such records, a possible workaround is to create a view in mysql
that converts such values to NULLs and then import from this
view instead of original table.
Merge branch 'master' of https://github.com/philipsoutham/py-mysql2pgsql