feat: possibility to set theme in PaperProvider

[souhe]

This PR adds a possibility to pass the default theme in PaperProvider. See the original Paper docs.

In addition to that I added missing animation theme property.

After those changes it is for example possible to create a theme based on a default one. Just like this:

// Theming.re let theme = ThemeProvider.( Theme.make( ~colors= Theme.Colors.make( ~primary="red", ~accent="blue", ~background=defaultTheme->Theme.colors->Theme.Colors.background, ~surface=defaultTheme->Theme.colors->Theme.Colors.surface, ~error=defaultTheme->Theme.colors->Theme.Colors.error, ~text="black", ~disabled=defaultTheme->Theme.colors->Theme.Colors.disabled, ~placeholder=defaultTheme->Theme.colors->Theme.Colors.placeholder, ~backdrop=defaultTheme->Theme.colors->Theme.Colors.backdrop, ), ~fonts=defaultTheme->Theme.fonts, ~roundness=4, ~dark=false, ~animation=defaultTheme->Theme.animation, (), ) );

and use it like this:

// App.re <Paper.PaperProvider theme=Theming.theme> <YourApp /> </Paper.PaperProvider>