Add (and slightly tweak) Wuzzy's Target Practice missions

Wuzzy's changes to stats for some of the training missions.

cont.

wrap explosions!

wrap sinegun

issue #848: Minor translation update for German (misc files)

fix some old code that assumes that a bullet under water is always outside land array - which is wrong (e.g. during sudden-death in previous releases, also weSea now) also removed usage of Gear^.Damage after "if Gear^.Damage > 0 then Gear^.Damage:= 0;"

small shell script that accepts hedgewars git revisions as parameters and will try to find the respective mercurial revision

remove redundant check

merge FreeTexture into FreeAndNilTexture