Switch to utf8mb4 encoding.

Fixes #66
SHOW_BLOCKS PAGINATION
- Get total count of blocks in a BlockBatch within showBlocks()
- Fetch perPage (500) blocks at a time
- Offset blocks fetch based on "?page=" querystring
- Pass currentPage and pages[] to templates/show_blocks
- pagination.mustache made for inclusion in show-blocks
- CSS counters added to style.css for numbering pagination links
- pagination.js handles detecting current page and navigating to others
- Remove 'theres_more' flag