Update charview.c - Rename 'clear' to 'chop'  #Issue801

In the Char View, Edit menu, the 'Clear' command is somewhat unclear and it would be more immediately understandable if it was called 'chop'

So changed ot from Clear to chop
Modified C_lear to C_hop in PO files
Merge pull request #839 from yesyayen/master

Rename 'clear' to 'chop'  #Issue801