FIX_XTICKLABELS will determine maximum allowed width of long XTickLabels and convert them into multiple line format to fit maximum allowed width

IN:
handle [optional] - axes handle (defaults to gca)
margins [optional] - relative margins width (defaults to 0.1)
texopts [optional] - cell array of addtitional text formating
options (defaults to {} )

OUT:
ht - column vector of handles for created text objects

This code was derrived from MY_XTICKLABELS by Pekka Kumpulainen
http://www.mathworks.com/matlabcentral/fileexchange/19059-myxticklabels
EXAMPLE:
figure;

bar(rand(1,4));
set(gca,'XTickLabel',{'Really very very long text', ...
'One more long long long text', ...
'Short one','Long long long text again'});
fix_xticklabels();

figure;

bar(rand(1,4));
set(gca,'XTickLabel',{'Really very very long text', ...
'One more long long long text', ...
'Short one','Long long long text again'});
fix_xticklabels(gca,0.1,{'FontSize',16});

Mikhail Erofeev 07.06.2013
Pekka Kumpulainen 12.2.2008