Ignore lib directory

Change-Id: I68f3d2e095c854e79a27d6e6edbac760872a8bd2
Reviewed-on: http://gerrit.dmdirc.com/2396
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Chris Smith <chris@dmdirc.com>

.gitignore

@@ -2,6 +2,7 @@
 
 /build
 /dist
+/lib
 build-before-profiler.xml
 /nbproject/profiler-build-impl.xml
 /nbproject/private