fixed save as directory and file name, save directory afterward

previously save as was setting the default file name to "." in whatever
directory (this was an attempt to set the directory to the current
working directory, but "./" should have been used)

save as now sets the default file name to the current program is set (a
warning will be issued when attempting to save to this file), otherwise
sets it to the current directory (if program is untitled, and the file
name in the save dialog will be blank)

afterward, the directory of the file name saved to is saved in the
current directory member variable (and saved in settings upon exit)


set current directory when using save as

set save as directory and file name for file dialog
updated files for release 0.3.3

updated the README file for the latest changes
fixed copyright year in LICENSE and CMakeLists.txt