libpredict: add library to handle heal predictions

* move "prediction" from module into a library
* reduce the resize and trigger calls on unitframes
* improve performance by caching frames and events
* introduce later API commands such as:
    - UnitGetIncomingHeals(unit)
    - UnitHasIncomingResurrection(unit)
* update unitframes to make use of new api calls
* delay spell cache loading to not overwrite previous
* remove all unitframe specific code from library

init/libs.xml

@@ -8,4 +8,5 @@
   <Include file="..\libs\libtooltip.lua"/>
   <Include file="..\libs\libhealth.lua"/>
   <Include file="..\libs\libtotem.lua"/>
+  <Include file="..\libs\libpredict.lua"/>
 </Ui>

init/modules.xml

@@ -12,7 +12,6 @@
   <Include file="..\modules\addons.lua"/>
   <Include file="..\modules\minimap.lua"/>
   <Include file="..\modules\panel.lua"/>
-  <Include file="..\modules\prediction.lua"/>
   <Include file="..\modules\player.lua"/>
   <Include file="..\modules\focus.lua"/>
   <Include file="..\modules\target.lua"/>