Issue #750

Stop swimming against the tide and accept what most of the rest of
the world does.

While it adds an annoying depth to the actual source code, it makes
the root directory nicer (no more 'test-res' dirs), means we don't
have to override the gradle config, and makes it nicer to work in
IDEA 2016.1.

This does the reading/writing logic that's common to the other
stores.

This handles applying a function to each item to convert it to
the desired type, removing a tiny bit of duplication.

This allows it to be used to read other files, such as bundled
defaults.

Change-Id: I1db09ccf6e8048e00e8c73da4962f68c8bb8fb85
Reviewed-on: http://gerrit.dmdirc.com/3555
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Build Manager

Also statically import precondition methods randomly.

Depends-On: I49ec46315f1366d27c12d1b4cc2ac92cd479d46d
Change-Id: I2285d5b886d49841c3e5e6645da14a1c880e6745
Reviewed-on: http://gerrit.dmdirc.com/3535
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>

Change-Id: Ic51f6ca303a77cf0510780ba043402105381c04c
Reviewed-on: http://gerrit.dmdirc.com/3521
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>

Change-Id: I24afd60eecf5d77e8ecaf23de584243806df8fdd
Reviewed-on: http://gerrit.dmdirc.com/3519
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>