Merge pull request #13 from sstupka/master

DATABASE
cleanup and and images renamed to lowercase
Made a lot of changes to the database file. A lot of units were missing,
and there were a lot of general syntax errors (mostly from missing
information). Many of the equations are still wrong, and several of them
are jsut zero since they were not present but needed to be for
compilation. Fixed references to nonexistent pictures in the database.
Removed apostrophies in the names of variables (Java was having none of
it).
The units should be double checked in the database file, but it is way
more important to check the equations at this point; judging by the number
of syntactical errors I found, and by a quick glance at a few euqations, I am
guessing most of them need to be checked again.
Fixed an error where the code generation was not strict enough in its
definition of whether a string was already defined in the strings.xml
file.
Added an internal exception for the variable theta, since java was having
none of a literal with unicode in its name. I extrapolated the issue to a
dictionary, so further exceptions can simply be added to that same
dictionary.
Updated the units to be inclusive of all used units.