View source for Kexi/Junior Jobs/Simple Form Widgets

'''Status: done'''
<div style="float:right;padding:1em;">http://dot.kde.org/sites/dot.kde.org/files/GCI_2011_logo_URL_blueborder-nowww.jpeg</div>
Implement these widgets:
*OPEN, DIFFICULTY=3/5 Command Link Button (based on KexiCommandLinkButton from
kexiutils/), no data type
*OPEN, DIFFICULTY=5/5 Slider (based on QSlider), should bind to column of data type: int
*OPEN, DIFFICULTY=5/5 Progress Bar (based on QProgressbar), should bind to column of data type: int, user of course cannot change its value by clicking on it
*OPEN, DIFFICULTY=5/5 Calendar (based on KDatePicker), should bind to column of data type: QDate

* Recommended for [http://www.google-melange.com/gci/homepage/google/gci2011 Google Code-IN] program

*Required skills: basic Qt, average C++
*Work within a new branch kexi-widgets-shreya, please create. 
*All these widgets should be provided by plugins/forms/kexidbfactory.cpp and have implementation in individual files in plugins/forms/.
*Look at how Kexi's button widget is implemented/exposed in forms (for non-data widgets)
*Look how text line edit is implemented/exposed in forms (for data widgets)

Notes to mentor:
*Please always emphasize importance of coding style to students and check that - it's so easier to maintain the style from day one instead of fixing afterwards. Show [http://techbase.kde.org/Policies/Kdelibs_Coding_Style Techbase articles] for that.
*Take care of coding practices too (see [http://techbase.kde.org/Development/Tutorials/Common_Programming_Mistakes Techbase articles])