Improve rendering speed

[yinsee]

improve page turning speed by hiding invisible pages

[ivanlikov]

Can you please merge it as we want to use the better code, does this get support or not?

[mabDc]

it works nice when it is hundreds of pages which content is painter in canvas ( performance huge improved

[mabDc]

i found another better way : use only one AnimationController and only one PageTurnEffect, and in class PageTurnEffect get the current page and isForward to painter one or two page[s]

[Mu7ammadRasul]

i'm so sad that i thought I have found a good package, despite how nice it works after all of this but still it has some serious issues and seems like they are not into fixing them, the resolution of widgets is worse than my iphone 5 and some other issues will make you just decide no to use the package, hope they fix it in near future, still want to know how to fix the resolution and when the app runs it needs a hot reload to load widgets specifically images i used.