Replacement of bitmap icons with SVG icons

[shinsenter]

This can help reduce the size of the package after it is compiled.
Related to the issue #17.

@mattermoran
TODO: SVG files are temporarily added. Replace them with better SVG files.

[mattermoran]

Hey @shinsenter
It seem to work fine but the only problem I have with it is that it takes about a second before the icons actually show up. I guess that's because it needs to parse the svg files first but that's not very nice experience. I wonder if we can somehow speed it up so they show up instantly like pngs

[mattermoran]

Actually I have just tried to use svg path and pass it directly to SvgPicture.asset and in that case it seems to be instant.
So it looks like _SvgImage is being slow

[mattermoran]

Seem to be fine with the flutter_svg_provider package as well. We might wanna roll with that but that's another extra dependency

[shinsenter]

@mattermoran
Because you want to not change the interface of the current version, I have to workaround to change the data type of map.icon from PictureProvider to ImageProvider, so there will be a little delay when rendering the icons.

It seems that the size of the icons affects the rendering speed, I will try reducing the size of the icons to 256pt (currently 1024pt).

[shinsenter]

@mattermoran
Please review again

[mattermoran]

Looks way better now. Still not as fast as pngs but there's just milliseconds difference so it's fine. I will be merging this now, then update the icons and make a release. Good job!

[shinsenter]

@mattermoran
Thank you for approval.
I think it will be faster in production mode (tested).

[mattermoran]

hey @shinsenter
version 0.7.1 with your changes is available on pub
thanks for help!

[shinsenter]

@mattermoran
Great! Thank you

[aseef17]

Why was the intl package added as a dependancy ?

[mattermoran]

@aseef17 probably by mistake. I'm pretty sure I removed it in an actual release