switch to transifex for managing translations

english source files are stored at data/en.yaml
`make translate` pulls in updated translations
Use icons for additional fields
add tooltips to add-field buttons
Merge pull request #1027 from systemed/transifex

switch to transifex for managing translations
Add translation chart to readme
add translation instructions
remove locale/*.js from makefile
add yaml file for preset translations
move core.yaml to data dir
add additional fields for amenities and shops
Use traditional marker shape for points (fixes #172)
update translations
fix translations in packaged install
Refine tagged vertex rendering

Don't render tagged vertices for which we don't have
an icon as the 'marker' icon. Marker shape is for points.
Fields now have an optional geometry type

field defaults aren't geometry specific
the geometry type determines whether
that field (and default value) apply
to an entity
Fix phone/telephone confusion
Add missing label translations
Pretty-print to make merge conflicts less likely
add additional fields to most presets
Add vertex geometry to many presets