Ignore all Maven target & Eclipse specific files

Before this fix not all Maven multi-module build output directories and
Eclipse IDE specific files were ignored.

This patch fixes .gitignore to have them all properly ignored.

Issue: #68
Before this fix maven and eclipse specific files we
Upgrade logging dependencies

Before this change logging dependencies were a bit outdated.

This patch bumps up versions of logging dependencies to latest ones.

Issue: #69
DRY out surefire version

Before this change almost every submodule repeated maven surefire
plugin version.

This patch make surefire version information DRY by configuring it in
root parent pom only, and inherited by all submodules.

Issue: #70
Configure logback as slf4j binding for tests

Slf4j is used as logging api. NoSQLUnit users are supposed to provide
appropriate bindings. Because such binding was not provided to tests
in NoSQLUnit itself, build output was littered with "Failed to load
class org.slf4j.impl.StaticLoggerBinder" messages. For more info see
slf4j documentation: http://www.slf4j.org/codes.html#StaticLoggerBinder

This patch introduces logback as binding for tests in NoSQLUnit itself.

Issue: #71
Merge pull request #71 from sslavic/71

Configure logback as slf4j binding for tests
Merge pull request #70 from sslavic/70

DRY out surefire version
Merge pull request #69 from sslavic/69

Upgrade logging dependencies
Merge pull request #68 from sslavic/68

Ignore all Maven target & Eclipse specific files