Make small fixes on developers' testing page.

Main problem was the OmeroPy path which was simply wrong.
Use canned styles following sbesson's suggestions.

also cleaned up some whitespace
Fix test class links, per sbesson's suggestion.
Ressurect the ArrayColumn documentation

This reverts commit 48f3a5c3bb4b1b25e1306c93a50b30a68388c39b.
Added doc for FloatArrayColumn
Add clarification that Float/Double/Long are 32/64/64 bits
Remove long from values type since it applies to multiple column types
Merge pull request #277 from mtbc/fix-test-doc

Make small fixes on developers' testing page.
fixed width -> fixed-width
Merge pull request #279 from manics/tables_arraycolumns_9957-2

Tables ArrayColumn docs 9957