Use compression when store the scripts instead of saving the base64 string

[xcv58]

As mentioned here: #32 (comment)

We can use compress/decompress to save space.

I did a simple test via LZ-UTF8. It can save more than half-space.

We need to:

1. Find the best fit compress/decompress library that can compress/decompress string around ~4 KB fast enough. (We need to do compress every time user typing)
2. Add helper functions to deal with the storage for base64 and the new compression approach and add the ability to extend for other storage options in the future.