Filter list (left side panel) in WebUI is implemented using <a> tags,
CSS defines default style for all <a> elements, and specific style for
filter list elements. Default style for <a> elements sets color, and
this color also used in list. This is looks not so well. So lets just
inherit text color from parent element, and as so as it is not set, so
default text color will be used.
This makes filter list looks like other UI elemets, making all UI more
consistent (like in desktop app).
1. Use unified function names `initInstance()` and `freeInstance()` and
make them public.
2. Add `freeInstance()` to avoid noise from memory leak detectors.
3. Let `instance()`return a pointer directly to avoid unnecessary
indirections when invoking functions.
This will allow browsers to get high quality icon with required
resolution instead of resizing some small raster image.
Browsers can have even more benefit from it. For example, Firefox uses
high resolution icon to display it in "Top Sites" instead of page
preview.
Nothing changes for browsers which doesn't support SVG favicons, older
PNG icon will be used in such case.
The basic idea is to hash each class member and then mix them with xor
operation.
However the `seed` must be handled with care, it should only be
introduced once when mixing the hashes of each class member, otherwise
under some circumstances the `seed` might xor with itself and thus break
the intended effect.
When the CMake system was last revamped, the configure variable was
changed from WEBUI to DISABLE_WEBUI, but we are still checking
against WEBUI. This behavior was changed in fa770871e9
Model returns string for DisplayRole.
Text alignment is set by Model (using TextAlignmentRole).
Delegate performs custom painting only where necessary
(i.e. for Progress bar).
Don't sync main data if a request to do so is already in progress.
This prevents piling up of requests and bogging down slow/busy machines, since the current implementation of `/api/v2/sync/maindata` is very computationally intensive, especially with lots of torrents.
Everything gets updated on the next scheduled request anyway (via the timeout mechanism).
