ptwt v.0.1.6

What's new:

• support for symmetric padding for all convolution-based transformations (the default in pywt).
• channel dimensions are now automatically processed along with batch dimensions for 1d and 2d code for easier integration into machine learning models.

What's Changed

• Speed tests by @v0lta in #55
• Update readme.md by @v0lta in #56
• channel folding by @v0lta in #62
• V0.1.6 by @v0lta in #63

Full Changelog: v0.1.5...v0.1.6