[phobos] enforce() in std.container.Array

[David Simcha]

I'm looking to try out std.container.Array for a few huge arrays that 
the GC isn't cutting it for.  I noticed that this container is always 
bounds checked via enforce().  This has huge performance costs:

import std.stdio, std.container, std.datetime;

void main() {
     Array!uint arr;
     arr.length = 10_000_000;
     //auto arr = new uint[10_000_000];
     auto sw = StopWatch(autoStart);
     foreach(i; 0..arr.length) {
         arr[i] = i;
     }

     writeln(sw.peek.milliseconds);
}

This benchmark takes about 86 milliseconds with -O -inline -release.  
When I use the builtin version instead (comment out the 
std.container.Array stuff and uncomment the uint[] stuff) it only takes 
about 18 milliseconds.  Should I change front(), popFront(), opIndex(), 
etc. to be templates that use assert and give the caller's line and file 
on failure, just like regular builtin arrays?