Bug fixes and misc improvements

3.1.0.5

• Added PriorityBonus to entities.
• Separated drawing children into a virtual function so users will be able to override it.
• Replaced 'Disabled' property with 'Enabled' (but Disabled is still supported just deprecated).
• Fixed text entities to allow using spaces as placeholders with auto anchoring.
• Made text entities slightly more efficient in performance and memory when changing value / calculating size.
• Fixed Min/Max size with paragraphs and text entities.
• Changed order of MouseDown / WhileMouseDown and MouseEnter / WhileMouseHover events.
• Fixed dropdown not to close if dragging scrollbar outside boundaries.
• Added some helper functions to Input Helper.
• Added exception when trying to use non mono-space font, which is not supported.