Histogram importing

Added a new command, 'lhist', to allow the importing of histograms
from an external root file. Included new LoadHist methods inside
Plotter1D and Plotter2D to make this possible.

Added an entry counter display to _fill_hist methods inside of
Plotter1D/2D. If the number of entries is greater than 1M for 1D
or 500k for 2D plots, _fill_hist will display the current entry
number for every 10% of entries.

Added a new FSclass object in Framework to allow for version tracking
of FightingSquirrel classes. Updated all FS classes to inherit from
this new class.

Split Framework into a header file and a source file. Modified
Makefile to build Framework.o in addition to other object files.
Previous Command Recall

Added an array of strings to Executable to allow the saving of
previous commands. These may be recalled by typing '.r' at the
prompt. Typing '.r index' will execute the command at that index
in the command array.

Changed some reserved executable commands. 'help' has been changed
to '.h', and 'version' has been changed to '.v'. '.q' has been
added as an alternative to 'end'.

Added some new reserved executable commands. '.r index' will recall
previous commands to the screen. Executing .r with an argument
will execute the command at that index in the array. '.s filename'
saves the previous command array to filename. '.l filename' loads
previous commands from filename and executes them starting with the
last command in the file. Command files may be any length.