Add macros to check for the GTK version to build against
Check for the GTK version to build against
commander: Add support for GTK3
GeanyGenDoc: Add support for GTK3
WebHelper: Add support for GTK3
Disable plugins that check for a dependency on an incompatible GTK
Mark plugins that don't build on GTK3 as requiring GTK2

Plugin authors should remove or adapt this check when they port their
plugin to work with GTK3.
Small fix at German translatation which caused a segfault on GeanySendMail if no mailer and/or filename placeholder has been configured
Rework TableConvert-plugin to be a little more generic.
Purge unneeded code
Added testfiles
Fix possible memory leaks
Use correct callback function
Improve way how worker is being called. Thanks to b4n and elextr.
Fix a few small bugs.

* Change 'uint' typo to 'guint'.
* Change accidental hardcoded default_value.
* Add wrapper function for g_object_class_install_properties since
  it's only available since GLIB 2.26.
* Make PROP_O equal zero because it's always supposed to be zero.
Update HTML help file with slightly changed doc-utils output
Make rule-parameter const
Merge pull request #82 from frlan/Tableconvert_more_generic_rework

Tableconvert more generic rework
scope - documented changes by other developers
GeanyMacro: Fix a little typo reported by Lucas Vieites