typos in 6.1

[hiroyachiba]

Fixed some typos and bugs.

[fchollet]

Thanks for the PR! Ok for the typos, but the rest of the fixes aren't actual issues. Please restrict this PR to the typos.

[hiroyachiba]

First of all, thank you very much for the wonderful book!
Is it better to send small PRs separately?

Let me explain each PRs and could you correct me if I'm wrong?

1. Use the same seed_text for each temperature.
   In 8.1-text-generation-with-lstm.ipynb,
   All outputs in the book starts from the same seed text (ex. new faculty, and jubilation ...) for each temperature (0.2, 0.5, 1.0) and I thought this is the expected behavior.
   If you run the program (8.1-text-generation-with-lstm.ipynb), the seed text is different for each temparature.

2. Removed redundant image resize.
   In 8.2-deep-dream.ipynb,
   'resize_img(original_img, shape)' has already been called four lines above, so, no need to call it again.

   same_size_original = resize_img(original_img, shape)
   lost_detail = same_size_original - upscaled_shrunk_original_img

   img += lost_detail
   shrunk_original_img = resize_img(original_img, shape)

3. 8.3-neural-style-transfer original_image -> target_image, typos
   In 8.3-neural-style-transfer.ipynb,
   'original image' and 'target image' were used to mean the same thing, but
   the real point is the following part is typo.
   "while content(generated_image) would be close to content(generated_image)"

[hiroyachiba]

Restricted this PR only to typos.

[fchollet]

Thanks!

[ghost]

typo