added two item to the TODO list
added a bumpversion for the __init__.py file in the batchcalc
 corrected the basic template to typeset the pdf witout errors
separated the tests for the reactant class into a new file
added the "-halt-on-error" option to the subprocess Popen call to prevent
pdlatex process from waiting indefinitely for user input in case of error
also switched to the "call" instead of "Popen" since the output and error
are not really needed
corrected the succes dialog message for generation of the tex->pdf file
added two dialog to add a Chemical and Component to the database
and menu item for them in the main window, but they don't do anything
at the moment
* added the PhysicalFrom and Electrolyte classes
* added methods to expose the contents of the types, categories,
  electrolytes and physical forms tables
* added a common method to the reactants to check if a record/item
  is empty, None, NULL
* improved the labeling functions for ex and html labels
added a test file for the zbc gui but there are no tests there at the moment
small changes,
 small changes
added a dialog and menu entry to add a record to the batch table in the
database, the method is not doing anything at the moment