add SQL Anywhere configuration documentation
Enhancement: expose ping() on pingable-connections.

This PR introduces a new PingableConnection interface and exposes
a ping method on \Doctrine\DBAL\Connection. For drivers where no
ping is supported, a \Doctrine\DBAL\ConnectionException is thrown.
skip unsupported test on SQL Anywhere
Fix Exception converting into a non-BC change.
implement SQL Anywhere driver exception conversion
return 0 by default for exception conversion
make driver method for constructing the DSN private
wrap driver connection exceptions
rebase with master
Merge pull request #415 from deeky666/skip-unsupported-tests-on-sql-anywhere

Skip unsupported tests on SQL Anywhere
Merge pull request #412 from deeky666/add-sql-anywhere-documentation

Add SQL Anywhere configuration documentation
fix driver implementation
readd use statment
Merge pull request #411 from deeky666/add-sql-anywhere-driver-exception-handling

Implement SQL Anywhere driver exception conversion
Bugfix: coding standard & missing assertion
Enhancement: implement ping() for all drivers

 * h/t @stof and @deeky666
 * add two test cases for the general connection test
 * remove the ConnectionException method I added originally
Forgot removing method from Driver interface, documented ExceptionConverterDriver better.
Fix postgresql test on travis
Enhancement: CS fixes

 * license
 * author tags
 * doc blocks
 * new lines
Enhancement: use connect() to simplify the test