Set css class and border size for html tables.
Merge branch 'master' of github.com:3dna/api_docs into miki/improve_datatable_conversion
Move the generated tabel header row down to the body.

The 'table-docs' css class will make the first row look like a header.
Having an explicit table header means we effectively get 2 header rows.
Do not remove the header rows except the first one.

The first row is usually the same as the page name in NationBuilder and the CMS will display it.
The other header rows contain valuable information and should not be stripped.
Merge pull request #28 from 3dna/miki/improve_datatable_conversion

Improve api_docs md->html script to eliminate manual steps