show <constant> if the state variable is constant

Fix source location highlight for code that use sol lib

Update tutorial_remixd_filesystem.rst

Add remixd tutorial

Fix solidity state

Improve mapping decoder

misc: Add link to example Dapp Front End. Add Geth block check command. Fix typo.

initial support for mapping types

- add we3.debug.preimage
- move mapping resolver from soliditystate to storageViewer

version change

eventManager as lib in index.js