Move evaluateScript into QV4::Script

also remove an unused method in QV8Engine

Change-Id: I1e655e714755426ac0c48ee9cc08059104ddb3b3
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Remove QV8Engine::scriptValueFromInternal

Change-Id: I43d672d17c0bbb498be71d7a25f8ca1389aeadf7
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Various fixes

Fix a regression in Script::run, and compilation for
v4 and an auto test.

Change-Id: I4026eebec0e02f4af03ca49ba714916ad90b34e7
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>