Adjusted to new failure return types in sqlpp11

Fixed test issue on Appveyor.

Admittedly, I am not really sure why this fixed anything (re-ordering of header files), but I happy to see that the code compiles, links and runs fine now on a Windows machine.

Support for sqlcipher

Test write/read pragma values

Fixed call to floor for MSVC

Fixed compilation error (MSVC)

travis/appveyor integration started

Fixed date.h incompatibility

Adjusted to changes in sqlpp11-0.36

Sync release with sqlpp11

Added attach method (support for schema qualified tables)

Minor fixes