Drop '-no-opengl' Qt configure argument for OS X

Compilation for -no-opengl on Mac OS X only got fixed in 5.4, qtbase
commit a12ba316161b23b .

Change-Id: I74d2cfd6b42c673ee72fbd4977eda92a82618748
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>
Replace 'configure options' by 'configuration options'

This makes INSTALL in line with getting-started.

Change-Id: I36e1141785c9068c03f653aa2d3d6cd3c347159e
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>