add features: pause and resume recording video

[digitalmidges]

Add 2 new features: Pause video recording and Resume video recording

[alaegin]

@natario1 Hello! How about integrating these changes into the library? We need it. The MediaRecorder methods pause and resume have the api24 requirement but it's possible to add such requirement to library methods so we don't need to upgrade minSdkVersion.

What do you think?

[natario1]

I have nothing against the feature, but this PR has too much clutter, unneeded changes, no javadocs, no docs, no tests, no PR description about design decisions (e.g. I changed this to this and used this to solve that problem because...), no reference issue / discussion. I can't afford to take care of any of this. The less lines you change, more polished you present it, more test coverage you add... more likely I can actually take a look.