insert select statements
Merge pull request #17 from snoyberg/master

hspec 1.6
Bump version to 1.2.2.1.
No more MPTCs, added documentation
Merge pull request #16 from bogiebro/master

Insert select statements
Final touchs on docs.
Bump version to 1.2.3.
common math and aggregation sql functions
Merge branch 'master' of git://github.com/meteficha/esqueleto
fixed a typo
added tests for math and aggregation functions
Merge pull request #18 from bogiebro/master

Adding some common functions
Bump version to 1.2.4.
Add unit test for ordering using random_.
Make max_, min_ and sum_ less general.
Proper NULL handling in max_, min_ and sum_.

- return expr (Value (Maybe a))
- add joinV to join nested Maybes in an expr
Handle NULL result in avg_ too.
Merge pull request #22 from db81/less_general_max

Less general aggregate functions and NULL handling.
Bump version to 1.3.
Fix comma.