reaname traits

[GioBo]

Adopt trait names which are more consistent across traitbases; eg for flowering period we now have

• flw_beg
• flw_end
• flw_early
• flw_late
• IT_beg_flow
• IT_end_flow
• beg_flow_fr
• end_flow_fr

Should follow a single template: beg_flow_country

For life form:

• li_form
• life_form_P
• li_form_B