Remove unnecessary `Str` and `Vec` prefixes on relevant iterators

[alexcrichton]

Iterators in the str module are all prefixed with Str, but this isn't really necessary when you're using them as they're imported like str::StrCharIterator, something like str::CharIterator makes more sense.

There's also a similar situation in the vec module where they also need to be renamed.

[thestinger]

+1

[alexcrichton]

@jmgrosen, is there a reason that these iterators weren't renamed?

• StrSplitIterator
• VecIterator
• VecMutIterator

[jmgrosen]

1. I wanted to differentiate it from CharSplitIterator (StrSplitIterator actually used to be named StrStrSplitIterator)
2. Iterator is a lang builtin
3. I wanted to keep the mutable iterator consistent with the immutable iterator

[alexcrichton]

I agree with 3, I guess 1 is fine, but for 2 I think that vec::Iterator is different enough from iterator::Iterator that it could warrant having the same name. It'd be nice to drop the prefix as well, but others should probably weigh in other than me.

[jmgrosen]

I guess I didn't realize that it was possible to name something the same thing as a lang item, so I guess that's my fault there. Should I make another PR for vec::VecIterator -> vec::Iterator and vec::VecMutIterator to vec::MutIterator?

[alexcrichton]

I'd r+ it!