Extract GPS heading from EXIF for {{Location}}

This enhancement is available for users of a Lightroom (LR) version 6 or
higher. The function to retrieve the direction has been introduced by
Adobe with version 6. Therefore this enhancement is not available by
users of versions lower 6.

This enhancement differs several LR versions. Depending on the version,
different information messages are shown (or not):
* LR 6 or higher: If the `Direction` field is set, the user gets
  informed about this feature. Uploads of files without a direction
  setting don’t cause this information message, because at such cases
  the user is not affected.
* LR 5: Users get informed, the feature is not available, due to the
  insufficient LR version. Adobe introduced the “Direction” field with
  LR version 5, but forgot to include it at the corresponding LR SDK 5.
  Therefore this feature can not be used by users of LR 5. At release
  notes of LR SDK 6 this has been mentioned to be a bug fix of LR SDK 5.
* LR 4: Users of this version are not affected, because Adobe introduced
  the “Direction” field with version 5. Therefore users of LR 4 don’t
  get any information message.
* LR versions lower 4: These versions are not supported by LrMediaWiki.

The information messages include a “Don’t show again” (German: „Nicht
erneut anzeigen“) checkbox. If the user decides, to set this option and
decides to revert this decision later, a reset of warning dialogs at LR
is needed:
* English: Edit -> Preferences... -> General -> Prompts -> Reset all
* warning dialogs
* German: Bearbeiten -> Voreinstellungen -> Allgemein ->
* Eingabeaufforderungen -> Alle Warndialogfelder zurücksetzen

LR can store a direction value with up to 4 digits beyond a decimal
point, but shows at user interface a rounded value without decimal
places (by mouse over the direction field). The information message
shows the same rounded value, to avoid confusion of the user seeing
different values. The `{{Location}}` template parameter `heading` is
filled by the stored value of LR. Sample: A direction input of
359.987654321 is stored as 359.9876, shown as 360°. At `{{Location}}`
template the LR stored value of 359.9876 is set.

Affected code:
  - MediaWikiExportServiceProvider.processRenderedPhotos:  use the
    heading value to generate the Location template
  - Info:  change SDK version to 6.0

Fix #35.

1 files changed, 1 insertions, 0 deletions

diff --git a/CREDITS.txt b/CREDITS.txt
index 98888ec..d771592 100755
--- a/CREDITS.txt
+++ b/CREDITS.txt
@@ -1 +1,2 @@
 Robin Krahl <robin.krahl@wikipedia.de>
+Eckhard Henkel <eckhard.henkel@t-online.de>