adjust :focus / :active for links in Docs pages

took the chance to remove some !important that had been accumulating
prepare to re-use hash builds
Untested builderHash load and save functionality.
Merge pull request #173 from SergioCrisostomo/fix-focusactive-links-in-docs

adjust :focus / :active for links in Docs pages
add testing samples
make builder save and load hash
improvements after review
Refactored the builder hasher

- now it adds the hash link to the download file, as it used to be
- improved error handling in the builderHash
- use a separate config file for the locations, so you can specify that
  in dev and production.
Make core/index not executable.
Move the BuilderHash from middelware to lib.
Rename middleware/buildHash - fix when the hash was not in the database

Fix when there are no results for loadHash
Merge pull request #1 from arian/restore-hash

Restore hash
remove unused placeholder span
Merge pull request #174 from SergioCrisostomo/restore-hash

Restore builder hashes.
lib/BuilderHash: Add hash to hashCount return value.

Fixes bug where insertIfNotExisting would always try to insert
(and error out on uniqueness constraints).
lib/BuilderHash: Use `path.resolve` instead of `path.join`, to allow for absolute paths.