Fix for tempo/time_signature at start with Score.clip method

[Mintas]

for details see:
#60
and
#35 (comment)

[Yikai-Liao]

events.filter([start, end, &sentinel](const T& event)

The compile error could be fixed like this. And I have fixed it in the main branch.

[Mintas]

@Yikai-Liao Thank you!
I hope that will fix the issue =)

I'm not very aware of the current release process, when can we expect a new version of Symusic?

[Yikai-Liao]

I will release the new version today. Sorry for the waiting.

I have just partially refactor the midi parsing code, which leads to a nearly 60% acceleration. You could see the benchmark results here. Yikai-Liao/symusic-benchmark#1

And I have just finished cleaning the code and replace all the Chinese comments by English ones.