argparse module increases program versatility

The argsparse module adds a lot of command lien interface versatility.
Other than the default -h, --help optional argument, the programs adds
the common --version and -v, --verbose changes the level of output. The
output increases as the integer argument on -v, --verbose increases from
0 to 2.
Added options to command line

Add three new options to command line arguments:
-a, --alldatabase runs the program as before, BLASTing all databases
with all FASTA files.
-c, --contigs runs BLAST searches only on file sending with ".contigs"
-n, --nocontigs runs BLAST searches on non contig files.
These three options are required and mutually exclusive.
Edited program to only get root database name, i.e. database instead of
database.00, database.01, etc. This improves  speed and reduces results.