Run multiple iterations. Print final temperatures. Reduce stdout spew.

[Quuxplusone]

This makes the output of the program more closely resemble that of the
original Copycat described in "FCCA" page 236:

[T]he average final temperature of an answer can be thought of as
the program's own assessment of that answer's quality, with lower
temperatures meaning higher quality.

For example, running python main.py abc abd ijk 100 produced the
following output:

ijl: 98 (avg temp 16.0)
jjk: 1 (avg temp 56.3)
ijk: 1 (avg temp 57.9)

And for python main.py abc abd ijkk 100:

ijkkk: 2 (avg temp 19.8)
ijkl: 51 (avg temp 28.1)
ijll: 46 (avg temp 28.9)
djkk: 1 (avg temp 77.4)

[jalanb]

Apologies for slight delay, was offline on hols.

Thank you for the contribution, which enhances the code, and has been accepted