Merge pull request #23 from hkaelber/integration-master

Gletters: first version
planegame, a more robust move implementation

The helico move is more stable, no more random jumps on touch
screen. On the downside I removed the rotation effect and the
angle is not implemented on tablet.
created algorithm activity.
algorithm, improved code

- better code formatting
- use of common variables and model
- single sound item
algorithm, user interface major rework

Made the items dependend on the window size while keeping the ratio.
Reformatted the image items to be 100x100
Replaced the background image by a desert image from openclipart
Added port of the mosaic activity
Merge branch 'mosaic'
Published android beta 0.8
core, replaced QtQuick control 1.2 by 1.1

The 1.2 import is only available in Qt 5.3 beta. This is not a
good idea to force developers on it yet.
core, replaced QtQuick Window 2.2 by 2.0

The 2.2 import is only available in Qt 5.3 beta. This is not a
good idea to force developers on it yet.
algebra, minor removed extra focus=true
click_on_letter_up, minor removed an extra import
algebra activities, renamed qml in CamelCase
memory-math-mult, minor typo
advanced_colors, renamed qml in CamelCase
click_on_letter, renamed qml in CamelCase
erase, renamed qml in CamelCase
leftright, minor change in comments
menus, removed ported activities
core: add support for an on-screen virtual keyboard for mobile devices

This adds a VirtualKeyboard QML element meant for use on mobile. As
Androids own virtual keyboard accessible via Qt.inputMethod() can't
produce single key-events needed for some activities it has been
decided to implement a simple row based virtual keyboard on app level.

Its layout by now must be set via the layout property which is row
based. The qwertyLayout property provides a layout for illustration
and default purposes. Just assign it to layout for testing. The
keyboard is invisible and disabled unless a valid layout has been set.
Once visible it can be opened and closed by pressing on the drawer bar
(all plattforms) or sliding up/down (on mobile platforms).

Appearance can be  further adjusted by the following properties:

property bool equalKeyWidth: true
property int rowSpacing: 5
property int keySpacing: 3
property int keyHeight: 35
property int margin: 5
opacity: 0.9

Keypress events are signalled via the keypress signal which passes the
label string set at layout initialization.

Although meant to provide key input for mobile devices, it also
supports desktop systems.

A very useful future enhancement is support for a shift key. This
would reduce the amount of keys for layouts that contain both upper
and lower case letters.