fdo#55292 add middle wildcard autocorrection

Syntax: .*text.*, eg. for f-ligature replacements:

.*fi.* -> ﬁ (U-FB01)
.*fl.* -> ﬂ (U-FB02)

For en-dash replacements between numbers ("2014–15"), instead of em-dash:

.*1--.* -> –
.*2--.* -> –
...

Change-Id: I8992a751e2c1fbdd96a36cf555eb4349d5f80276