Fix assorted PMD errors.

Change-Id: I9af7e36f2aeb10bd658c5825ad2f94161e0bb243
Reviewed-on: http://gerrit.dmdirc.com/3940
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Build Manager

Change-Id: Ic0e6e5f95adc30e773945c95e73d321d589503d2
Depends-On: I8888522d58ff4d332c4a477702442c29a82d12ff
Reviewed-on: http://gerrit.dmdirc.com/3871
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Build Manager

Change-Id: I58e485b06887b1215b4d4cba7f2244404a7b81aa
Reviewed-on: http://gerrit.dmdirc.com/3869
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Build Manager

* Move all plugins to their own top-level directories.
* Move resources out of source trees
* Add Gradle build scripts.
* Remove ivy and ant build scripts.

Change-Id: Ib69a48ef26800c174ccf51c84ff9d1f73529460f
Depends-On: I303b6b69518468f98d48d835b8f40135d9e4bcbf
Reviewed-on: http://gerrit.dmdirc.com/3850
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>