MapRenderer: Do not call map_to_screen so often for Orthogonal maps.

Fixes #326 for orthogonal maps.
Add option for equipment to apply when transformed

In response to #448

With this, we can now use `keep_equipment=true` for flare-game's Stealth
power. The default value for this false to retain the old behavior and
avoid breakage with other games.
Use keep_equipment for Stealth power
Increase the size of the dot showing the hero on the minimap.
Don't invalidate iterators again!
Remove cppcheck warnings.
Merge pull request #459 from stefanbeller/largerheroonminimap

Increase the size of the dot showing the hero on the minimap.
Merge pull request #458 from dorkster/bugfixes

Add option for equipment to apply when transformed
Merge pull request #457 from stefanbeller/speeduprender

MapRenderer: Do not call map_to_screen so often for Orthogonal maps.
Merge pull request #460 from igorko/master

Don't invalidate iterators again!
Merge branch 'master' of https://github.com/clintbellanger/flare-engine
Stealth retains item bonuses
Remove placeholder item flavor
Update fantasycore and alpha_demo pot files.
Update engine.pot file.
Merge pull request #462 from stefanbeller/master

Remove cppcheck warnings, update port file.
Merge pull request #198 from stefanbeller/master

Update pot files.
Merge branch 'master' of https://github.com/clintbellanger/flare-engine
Merge pull request #199 from dorkster/fixes

Use keep_equipment for Stealth power
Recreate the actual *.po files as well. Add a script to do it automatically.