Added a somehow working calculator
Changed input method to CLI argument
Added System.exit to exception handlers
Added unusual token handling, fixed typo
Fixed some more typos
Fixed a bug with unmatched parenthesis error message
Removed unused import
Fixed reviewer notices
Fixed style issues
Added CLI utils and filemap
Enhanced interactive mode:

 - added prompt
 - fixed continuing of line with 'exit'
Enhanced command execution exception messages
Fixed whitespace handling
fabric -> factory. Such a shame.
Replaced many ifs with one switch
Added unexpected EOF check
Fixed dynamic mem allocation for reading
Merge branch '02-FileMap'