Fixed issues with the mIRC color serializing/deserializing

...quasseldroid_ng/ui/chat/chatview/ChatMessageRenderer.java

...de/kuschku/quasseldroid_ng/ui/chat/drawer/BufferItem.java

.../de/kuschku/quasseldroid_ng/ui/editor/AdvancedEditor.java

.../java/de/kuschku/quasseldroid_ng/ui/theme/AppContext.java

app/src/main/java/de/kuschku/util/irc/format/BoldSpan.java

...ava/de/kuschku/util/irc/format/IrcFormatDeserializer.java

...main/java/de/kuschku/util/irc/format/IrcFormatHelper.java

.../java/de/kuschku/util/irc/format/IrcFormatSerializer.java

app/src/main/java/de/kuschku/util/irc/format/ItalicSpan.java

app/src/main/java/de/kuschku/util/ui/MessageUtil.java