Remove EMSI Dependency and Allocator use

[burner]

This PR removes the use of the emsi container dependency
and the allocator.
This makes the code faster to compile and I couldn't measure
and performance difference.
The array/vector is very small after all anyway.

[cyrusmsk]

@burner would you like to add this package to dlang-community?
I found some bugs in it, so the package needs some work to move it to better shape and I think it is quite important to have such functionality in the D ecosystem. Or do we have any other similar libraries in dub?

[burner]

@cyrusmsk I forked it quite a while ago and removed the allocation and container dependencies.
The code can be found here https://github.com/burner/date-parser2
I'm okay with adding that package to the dlang-community