Adding targets for profiling, optimization, and code coverage
Added alternate implementation of string icmp

In Phobos uni.d implementation of icmp, it is noted that
the implementation given takes a performance hit to be
pedantically correct. This implementation assumes vanilla
string-like types, and necessarily puts the new implementation
at 1/4th as much total time-in-function compared to library icmp.
Small change that halves execution time of cpy ctor

Alleviates copy of large string, instead just points to
existing string
Formatting, added pure nothrow to simple functions
Merge branch 'optimizations' into allUnmergedFeatures
Added calling rehash for op hash, gives decent speedup
Merge branch 'optimizations' into allUnmergedFeatures