Move more ui init code to swing ui initialiser.

Depends-On: I9e67f7f9fbb479c13ff04fc237f2cb82c08a506c
Change-Id: Ia552a47b40002a346eaeabab3f757ecc32b12b68
Reviewed-on: http://gerrit.dmdirc.com/3317
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Chris Smith <chris@dmdirc.com>
Move MainFrame initialisation out of constructor.

Change-Id: If84baaa21a34335cd41e9b06bf4c693889cdfd76
Reviewed-on: http://gerrit.dmdirc.com/3320
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Chris Smith <chris@dmdirc.com>