Adds 'ClientPatternTest' command

ClientPatterns might be tricky to get right. Instead of fiddling around in
either the keys-file or the apps-file and restarting fluxbox to see if the
changes had any effect / matched the right windows, 'ClientPatternTest' and
the fluxbox-remote should make this easier:

    $> fluxbox-remote "clientpatterntest (title=.*vim*)"

This causes fluxbox to store the list of matched windows in the
_FLUXBOX_ACTION_RESULT property onto the rootwindow. This property might
then be read by:

    $> xprop -root _FLUXBOX_ACTION_RESULT

or

    $> fluxbox-remote result

The format of the list is:

    win_id \t title_of_window \n

win_id is '-1' when fluxbox wasn't able to parse the given ClientPattern.
win_id is '0' when there are no windows matching the given ClientPattern.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/FbTk/StringUtil.hh b/src/FbTk/StringUtil.hh
index 538828b..930e0b5 100644
--- a/src/FbTk/StringUtil.hh
+++ b/src/FbTk/StringUtil.hh
@@ -44,6 +44,7 @@ int extractNumber(const std::string& in, unsigned long long& out);
 
 /// creates a number to a string
 std::string number2String(long long num);
+std::string number2HexString(long long num);
 
 /// Similar to `strstr' but this function ignores the case of both strings
 const char *strcasestr(const char *str, const char *ptn);