Add support for existing benchmarking frameworks

[awadell1]

PkgBenchmarks.jl uses a single benchmark/benchmarks.jl file defining SUITE::BenchmarkGroup

This is similar to the example in https://github.com/JuliaCI/BenchmarkTools.jl/blob/master/benchmark/benchmarks.jl. But BenchmarkTools uses suite not SUITE

StaticArrays.jl uses PkgBenchmark's format but includes all benchmark/bench_*.jl files automatically (Yes, PkgJogger was inspired by this)

BaseBenchmarks.jl does not follow PkgBenchmark's format but does use SUITE