Better time formatting by using an explicit format

The default format QDateTime::toString uses isn't very good
Also make it possible for translators to change the format
Display timestamps using the application locale

Reverts configuration of timestamp formats via translation files.
Formatting of timestamps and such should completely move from core to client at
some point.
Fixes #1199
Only chop \r\n instead of trimming all whitespace

Any whitespace in front of the protocol's \r\n is part of the message
and thus should not be trimmed. Fixes #1197
Parse wallops (fixes Bug #1185)
Strip newlines from 'reason' fields in settings

These messages are sent to the server verbatim, which means anything
after a newline (which can be pasted into a QLineEdit) would be used as
a command.