Rewrote a lot of the components tree code:

- Added SF_PSELECTED for partially selected sub-sections
- SF_EXPAND now refreshes the components tree
- Fixed problems with sub-sections with RO sections as children
- (-1) sent to .onMouseOverSection when mouse over nothing
- RO sections can now be in InstTypes too (default to old behavior)
- Optimized code


git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@2436 212acab6-be3b-0410-9dea-997c60f758d6

Include/Sections.nsh

@@ -13,6 +13,7 @@
 !define SF_BOLD       8
 !define SF_RO         16
 !define SF_EXPAND     32
+!define SF_PSELECTED  64
 
 !define SECTION_OFF   0xFFFFFFFE