Remove Any bounds

[theotherphil]

Fixes #147

[theotherphil]

Is there anything blocking merging this?

[Andlon]

Hey @theotherphil, sorry, @AtheMathmo and I have both been very busy as of late.

A few brief comments:

• There is already an existing (unmerged) PR Issue #147 #171 which seems very similar. I haven't looked in detail at the changes, but I expect them to be almost identical.
• This is a breaking change, although a very minor one, so we need to decide if we can put it in a patch version or if we should postpone to the next minor version (though perhaps our next release is a new minor version)
• This PR also includes some functionality for in-place transpose, which is a little confusing since it's a separate issue. I was also lead to believe that this kind of functionality depends on some unavailable functionality in Rust atm, such as 128-bit integers?

[theotherphil]

Oops, I didn't mean to include the in-place transpose changes! I'd forgotten about this commit by the time I made the in-place-transform changes.

I hadn't seen the other unmerged commit. I'll close this pull request.

[Andlon]

@theotherphil: No worries! Thanks for taking the time to make the PR. I'm sorry that progress on merging contributions for this library has slowed down lately, especially considering the number of interested contributors. I hope to have some more time again myself soon (recently been focused on starting my new job in a new country, including all the paperwork and getting the apartment in order), which should help a little with the situation.