fix jpeg reading regression after #1805 - closes #2123 (patch from @clundgren)
fix relative paths in mapnik-config for fonts/plugins
fix linking order in svg c++ tests
fix linux linking order in python bindings
fix boost_regex icu detection on linux when statically linking
Revert "branch 2.3.x from master at v2.2.0-242-ge85cdda"

This reverts commit 9e66317af1de3ebe8205aaefebf42514ddf82f32.
add ENABLE_SONAME option + embed rpath/loader_path by default - closes #1225
Merge branch 'master' of github.com:mapnik/mapnik into expr-v2
Merge branch 'expr-v2' of github.com:mapnik/mapnik into expr-v2