test suite: new tests for installer

test suite: new tests for installer

Added tests of loading the DB initialization and
sampple data SQL scripts for every language
and MARC flavour combination defined in
installer/data/{dbms}.  Errors that the
new test class should catch include:

* SQL syntax errors in kohastructure.sql
* SQL errors in the sample data

For each language and MARC flavour combination,
all mandatory and optional scripts are loaded.

As of this commit, several errors are reported
by this test class; these will be fixed separately.

Signed-off-by: Joshua Ferraro <jmf@liblime.com>