Add python plugin paths

[ccrook]

This proposed patch to qgis.utils modifies the plugin loading to allow users to define additional plugin path locations (for example shared plugin folders). It allows these paths to be defined by a QGIS_PYTHONPATH environment variable, which can hold multiple paths separated by a semicolon. In each path it will look for a plugins folder, and in that each folder containing an init.py* will be treated as a plugin module.

[wonder]

Chris,

may I suggest you to use e.g. QGIS_PLUGINPATH - that would contain path(s) directly to the directory with plugins. Because QGIS_PYTHONPATH gives impression that one can override the whole python path and not just path for plugins. So, instead of QGIS_PYTHONPATH/plugins I suggest QGIS_PLUGINPATH

Martin

[ccrook]

Hi Martin

Good idea - I've updated the patch to do this. This does mean that I've changed the findPlugin function - it now looks in the directory it is given, rather than in the plugins subdirectory of that. However as far as I can see it isn't used anywhere else, so I think that this should be Ok.

Chris

[wonder]

Applied in r13236 with few modifications