WebUI: Add torrents paused because of errors in Paused and Download list

Torrents paused because of errors are considered as torrents paused and in
download in the regular UI. Do the same in the WebUI for consistency.

Closes #2319.
Fix sorting by port column in peers view.
Remove direct references to Qt4 in man pages
Merge pull request #2338 from jleclanche/master

Remove direct references to Qt4 in man pages
Merge pull request #2320 from pmzqla/webui-pausederror

WebUI: Add torrents paused because of errors in Paused and Download list
Add 'unpaused' torrent filter

the inverse of paused because complete and active have an inverse
Merge pull request #2321 from john-peterson/filter

adding inverse for paused filter
Fix Properties widget state saving

readSettings changed CurrentTab and Visible by calling saveSettings

some slot connections were wrong
Merge pull request #2322 from john-peterson/save4

fixing save state on change
HOTFIX: Correct command line parameters defaults.
Touch up previous commit.
Detect uknown command line parameters.