fix(solc): resolver and remapping auto detection bugs

[mattsse]

Motivation

Fixes several remappings related bugs, Closes foundry-rs/foundry#713

Solution

• handle contracts/src edge case as in @chainlink/contracts/src/{v.0.8, v0.9}
• handle edge case introduced in fix(solc): support remapping autodetection edge case #888 : distinguish between dapptools and hardhat style before merging multiple remapping candidates on the same level.
• better error message if a file couldn't be resolved
• fix import detection bug where imports in single quotes were ignored

PR Checklist

• Added Tests
• Added Documentation
• Updated the changelog