Merge pull request #11 from FreekDB/master

Mainly Checkstyle related improvements
Changed design of Zoom Panel to:
Zoom All TIC Charts - with In[+], Original, Out[-] buttons
Zoom X Axis - with prefilled values for min and max
Added support to gracefully update Report Viewer in case of 1) Changes
to the root folder; 2) changes to date range.
Removed reportNum from Main.java - Linked reportNum to
reportUnitsTable.size()
Processed (many of) checkStyle related suggestions by Freek. e.g.
Changed property PROPERTY_PROGRESS_LOG to PROGRESS_LOG_FILE_NAME in
Constants.java
Added TODO comment in Utilities.java and UtilitiesTest.java for
getNotAvailableImage() function.
Added TODO comment in Utilities.java and UtilitiesTest.java for
getNotAvailableImage().
Added error handling in Main.updateReportViewer() when no reports are
found in the root directory.
Resolved conflict after merge with master branch.