Removes npm postinstall command intended only for development of pack…

…age itself

Version bump and minor style adjustments

Adds a few badges

Updates version

Updates version

Adds option for selection of multiple dates and fixes issues with inj…

…ection of HTML

Fixes issue #12 and adds related unit test

Fixes issue #12 and adds related unit test

Fixes incorrectly implemeted test

Adds support for first day of week; minor bugfixes