Correct possible crash when clicking button/Ctrl while playback running.
Also lightlty simplify playback control
Merge pull request #166 from seandepagnier/master

a few errors now resolved when compiling particle map on windows
Correct introduced bug from 99fae02ed30f9bbf1055b27b493448fab772faa4

in GribRecord.cpp hasValue is used when reading the grib file, even
if the value is not defined.  It is also used in other places,
where it needs to test that the value is also defined.
Correct Tide/Current station selectable point logic (FS#1473)
Correct Tide/Current selection logic in Touch/Tablet mode.  (FS#1473)
Merge pull request #167 from seandepagnier/master

Correct introduced bug from 99fae02ed30f9bbf1055b27b493448fab772faa4
add "NPLDST" to list of possible National Language S57 attributes (FS#1464)
Merge pull request #165 from Ptizef/master

Correct possible crash when clicking button/Ctrl while playback running.
Correct calculated bearing for due North course from 360 to 000. (FS#1539)
Correct font selection logic for Chart Groups sub-menu (FS#1516)
Apply general User Font setting for grib_pi dialog
Work around OpenGL mipmap base level error in Mac platform drivers.
Bound underzoom of charts on piano selection with "Preserve Scale.." option set.
Correct PlugIn OpenGL overlay logic for API v1.12.
Merge pull request #170 from Ptizef/master

Apply general User Font setting for grib_pi dialogs
Bound CPU duty-cycle of GRIB Particle display rendering to 50%.
Update translations
Suppress chart outline and piano bar rendering for PlugIn charts when PlugIn is disabled.
Improve options->Charts progress dialog responsiveness.
Correct Route->Addpoint length calculation after undo (FS#1540)