po: Fix some typography issues in the Czech translation.

[Dan Kegel]

This patch found a bug in my scripts - it failed to grep the patch
for sender and subject - but it looks like there might be something
wrong with the patch itself, it doesn't apply here.

Buildbot said:
Full details are available at:
http://buildbot.kegel.com/builders/runtests/builds/194
BUILD FAILED: failed git

and here's what I get when I do it by hand:
$  wget http://source.winehq.org/patches/data/78249
$ git apply 78249

typocz.patch:31: trailing whitespace.
msgstr "Ověřte prosím, že název souboru byl zadán správně"
typocz.patch:40: trailing whitespace.
"Chcete ho vytvořit?"
typocz.patch:49: trailing whitespace.
"Chcete ho přepsat novým?"
typocz.patch:54: trailing whitespace.
msgstr "Nedovolený(é) znak(y) v cestě k souboru"
typocz.patch:63: trailing whitespace.
"Chcete ho přepsat novým?"
error: patch failed: po/cs.po:210
error: po/cs.po: patch does not apply