Improved company name autocomplete for person#new and #edit

Set a background color for highlighted search result for autocomplete.
Also fixed bug preventing a person from being assigned to an existing
company.
Autocomplete email mark field
Email marks autocomplete shows all marks on focus

When you focus on the mark field the autocomplete function drops down
the whole list of marks assigned to the field. The user can select from
the list or write their own mark.

Bug: Only works on field when document loads. Additional fields added
using "add email" links do not have autocomplete function attached.