Alina’s experimental sequences
the attribute iteritems() has been changed to items() for compatibility
issue with Python 3.3.2

write_to_log has been set ‘yes’ by default

out_file_1.txt , out_file_2 and log.txt where generated by the program
and have been added as references.
The find_motif function has been duplicate and revised in order to work
with both Python 2 and 3. The body of the has been implemented in order
to check which version of Python is running and to load the right
function as needed.
The code has been rewritten from scratch. No more merged sequences are
needed, no output files as well. It also search automatically for
motifs of length greater than motif_len.
Merge branch 'on-Alec's-iMac---Python-3.3.2-compatible'