Log Message:
wm/herbstluftwm: update to 0.9.3

-Fix transparency of 32 bit client's border (#1178)
-Prepare Colors for alpha values (#1180)
-Make default colors more transparent and quiet (#1185)
-Support true transparency in all decorations (#1186)
-Cut holes into frames behind tiled clients (#1187)
-'shift' moves between monitors if appropriate (#1198)
-Option --replace to replace existing window manager (#1209)
-Manage desktop windows in global stack (#1210)
-Start --locked from the .desktop file (#1222)
-Fix doc/gendoc.py extractor to strip comments (#1229)
-Use posix escaping in Completion objects (#1226)
-Remember last reported geometry in client directly (#1240)
-Always reply to a ConfigureRequest with ConfigureNotify (#1244)
-Move 'focus_edge' and 'shift_edge' to GlobalCommands (#1252)
-Allow relative values for int and uint attributes (#1253)
-Parse --skip-visible in move_index command (#1257)
_Make 'cycle' work for the floating layer (#1258)
-tox: Switch default Python env to 38 (#1269)
-New command 'list_clients' (#1274)
-Add client attribute 'floating_geometry' (#1272)
-Support error output channel internally (#1278)
-Auto-convert attributes to/from python types (#1277)
-Remove alpha-value from colors in panel.sh (#1283)
-Extend IPC protocol by error channel (#1285)
-client: Remove unused methods (#1291)
-Test herbstclient -0 --idle (#1294)
-Fix exec error message in spawn command (#1304)
-Wait passively for hc in test suite ipc server (#1306)
-Handle text properties more robustly (#1303)
-Test shift/resize up/left and focus cycling (#1308)
-Add 'floating_geometry' rule consequence (#1311)
-Client alias 'longest-minimized' and 'last-minimized' (#1313)