JBIDE-15017 CSS Editor dialog and CSS preview do not work on Windows 64

- Removed references to SWT.MOZILLA
- Wrapped <div> by <body> in preview. So the text can be at least alligned horizontally now
JBIDE-14735 Improve text formatting when dropping widgets from Palette view

Issue is fixed. Prev. sibling/parent tag is used to calculate the indent of the template text
that is to be inserted. 'Use spaces' option is taken into account. All indents that are inserted are
recalculated by using tabs (until it's possible) then spaces.
JUnit Test is added for the issue: org.jboss.tools.common.model.ui.views.palette.test.PaletteInsertHelperTest
Typoo in constant names are fixed