[Sailfish] Add landscape support

[RobertMe]

Currently all views on Sailfish and Ubuntu are still fixed to portrait only, but all need to become available in landscape as well.

Some things which need to be done:

• Convert all lists/menus to grids with multiple columns
• Investigate a way to show item details (long click on browser pages)
• Show gesture pad and buttons side by side (gesture pad on the left, buttons on the right, or other way around, possibly using a setting?)
• Rework now playing page
• Possibly add more information to controls dock

[mzanetti]

On Ubuntu the NowPlaying page already supports landscape, but rotation is disabled as a global app setting.

[mzanetti]

Also note, landscape mode does not necessarily mean a grid view is required. The switching between list/grid has more to do with the size of the display.

[RobertMe]

My plan is to "make this work" for the Jolla tablet. But I'll most likely hold back on adding landscape support till the SDK for Sailfish 2.0 is released. So I only have to build it once, instead of making it for the phone, and hoping it will also work for the tablet.

Ubuntu should be done independent of this (and I can't make it work for both). So I'll rename this issue to Sailfish and you could create your own then.

[dikonov]

Why is it necessary to convert lists to multicolumn grids? On a phone a landscape mode would help to read longer names of tracks that do not fit on a phone screen. It is counterproductive to lose the width by splitting it.