1.7.1

• Add JCS_OnMouseDrag function to check if the current mouse button is in the dragging action.
• Remove 'JCS_InputType' enum, is a mistake script by moving from other test module project.
• Update project/development version to 1.7.4.
• Update IO module's scripting manual.
• JCS_IO implemented for Input/Output utilities.
• Add JCS_Dropdown utility functions in JCS_GUIUtil module.
• JCS_Dropdown implmeneted for better dropdown UI handle.
• Add more dropdown util function in JCS_GUIUtil module.
• Add test option to JCS_3DLiquidBar.
• JCS_GradientText implemented for making the text gradient effect.
• Support load image as texture in image loader module.
• Change JCS_2DAnimation's displays variable from normal array to list data structure.
• Add active/play on awake/loop variable to JCS_2DOrderAnimPlayer.
• Add 'displays' variable in JCS_2DAnimation module for multiple
  JCS_UnityObject object displaying the same sprite.
• Add test key option on few effect modules/components.
• Add boolean check for if the specific joystick plugged-in util input function.
• Fixed slide input on focus changed the delta value issue.
• Add the test key option in JCS_GameManager.
• Show joystick names in the JCS_InputSettings' inspector.
• Add check all keys pressed/up/down and either key pressed/up/down.
• Add check all keys pressed/up/down and either key pressed/up/down with joystick too.
• Make legacy script for deprecated module => JCS_VideoPlayer component.
• Update Unity Engine version to => 2018.2.1f1.
• Implement remove empty slot to normal array in Util module.
• Audio loader module implemented.
• Video loader module implemented.
• Update scripting manual for audio/video loader.
• Add GUI util, for dropdown set to value function.
• Improve the usage of the dropdown set value function.
• Add test key in JCS_DeltaNumber script/component.
• Make current project version to 1.7.1.