Fix wxscheduler issues

[christiansandberg]

I just saw that you are planning on deprecating these schedulers but since I already made the fixes I'm making a PR anyway.

The Timer class used for scheduling actions has a few drawbacks:

• Timers can't be started from other threads, making operators like observe_on useless.
• Timers are quite slow. When doing an immediate schedule it is much faster to use CallAfter instead.

[dbrattli]

Hi, thanks for the PR. We are discussing if we should deprecate them so things are not decided yet. Activity is always a good sign of not deprecating.

[coveralls]

Coverage decreased (-0.04%) to 93.354% when pulling 25ba53f on christiansandberg:fixes-for-wx-scheduler into f35ee16 on ReactiveX:master.

[dbrattli]

Thanks for fixing. PS: You might want to also make a PR against the reactivex branch that will be the next version of RxPY (code name ReactiveX)

[dbrattli]

@christiansandberg Could I ask you to please update your PR against the latest v4 code, and I will make sure the scheduler will be part of the release and not be deprecated.

[christiansandberg]

Oh okay, I thought you would merge both to master eventually. I'll make a new PR.

[dbrattli]

PS: See instructions here for setting up the development environment: https://github.com/ReactiveX/RxPY#development

[christiansandberg]

Ok, I've rebased on top of master now.

[dbrattli]

Looks good. Thanks for fixing!