Add marker region decorator

[max-models]

Added a @profile decorator so that functions can be profiled with

@profile
def my_func(): ...          # region name = "my_func"

or

@profile(region_name="work")
def my_func(): ...          # region name = "work"

instead of using pylikwid.markerstartregion("work") and pylikwid.markerstopregion("work")

This PR branches from #28 , so if you want to merge this, then we should do it after merging #28 .

[TomTheBear]

Sounds like a good idea to use decorators.

[max-models]

Sounds like a good idea to use decorators.

I think it is. Actually, I already did something similar in a separate project where I basically wrapped the pylikwid marker start and stop like this: https://github.com/max-models/scope-profiler/blob/devel/src/scope_profiler/region_profiler.py#L303-L341

There, I profile regions using pylikwid either with a decorator or a context manager so for example:

with ProfileManager.profile_region("my_function"):
    call_func()

We ended up using this in struphy, see here, for example.

[TomTheBear]

Do you think this PR can be merged?

[max-models]

Do you think this PR can be merged?

Yes! To me it's finished :) Let me know if you need me to change anything. I just updated the readme and merged the last updates of master into this branch.