Crash

=================

- Added support for OPTIMIZE table statement.

- All statements will respond with an affected rows count now.

- Added a configuration file that stores default values for Crash. The file is
placed inside the user's application config folder.
A path to a custom configuration file can be specified using the ``--config``
command line argument.

- Dropped Python 2.6 support

- Added support for client certificates

- It is now possible to disable autocompletion using ``--no-autocomplete``
command line argument and to toggle autocomplete using the ``\autocomplete``
crash command.

=================

- Fixed "read file" command (``\r``) for legacy Python 2.7

- Fixed result info command output for whitespace other than space
characters in queries.

- Fixed call of `sysinfo` command when launching the shell.

=================

- The order of the keys / columns of the ``json`` output format is now
deterministic and reflects the order of the columns in the executed query.

- `Ctrl-c` no longer results in a KeyboardInterrupt exception if invoked while
a query is being executed.

- Added initial auto-completion support for the internal ``\format`` and
``\r`` commands.

- Added a new ``\r`` command which can be used to read and execute statements
from a file.

- Fixed an error that occurred under python 3 if one of the built-in commands
that require an argument were called without argument.

=================

- Added new format ``json_row`` which prints a dataset as json row-by-row
in separate lines.

- Added the ``sysinfo`` command which queries the ``sys`` tables for
system and cluster information. The command requires Crate.io >= 0.54.0

=================

- Python2.6/2.7 output now prints unicode strings correctly when using
csv output format

=================

- Fixed an assertion error that could occur under python2.7