Log Message:
Update to vimb-2.3.

Main Changes:
- Stop previous search before new one
- Fixed wrong download path for pages with trailing /
- Allow to complete multiple tags for :bma command
- Added async :shellcmd!
- Fixed none working 'F' hintmode for webkit2
- Use 'tls-database' instead of deprecated 'ssl-ca-file'
- Added wget style progressbar
- Simplified :shell command processing
- Added shell expansion for download paths
- Use new chartable instead of ctype
- Allow to set empty download-dir
- Don't expand download-path if set
- Fixed segfault of not shortcut default is set
- Added missed default shortcuts
- Allow to copy link location via context menu
- Fixed segfault on open new window via context-menu
- Allow to built vimb with webkit < 1
- Fixed none working open hints in new window
- Adapt zoom level for high dpi displays