DIRECTGOLib - DIRECT Global Optimization test problems Library

Added 69 new box-constrained global optimization test problems to the previous version v1.1:

• AckleyN2.m, AckleyN3.m, AckleyN4.m, Adjiman.m, AlpineN1.m
• BartelsConn.m, BiggsEXP2.m, BiggsEXP3.m, BiggsEXP4.m, BiggsEXP5.m
• BiggsEXP6.m, Bird.m, Brad.m, Brown.m, Bukin4.m
• CarromTable.m, ChenBird.m, ChenV.m, Chichinadze.m, ChungR.m
• Cola.m, Cross_function.m, CrownedCross.m, Cube.m, Cubic.m
• Dejong.m, Dejong5.m, Dolan.m, Exponential.m, Exponential2.m
• Exponential3.m, Giunta.m, Hartman4.m, HelicalValley.m
• HimmelBlau.m, Layeb01.m, Layeb02.m, Layeb03.m, Layeb04.m
• Layeb05.m, Layeb06.m, Layeb07.m, Layeb08.m, Layeb09.m
• Layeb10.m, Layeb11.m, Layeb12.m, Layeb13.m, Layeb14.m
• Layeb15.m, Layeb16.m, Layeb17.m, Layeb18.m, Leon.m
• Levi13.m, ModSchaffer1.m, ModSchaffer2.m, ModSchaffer3.m, ModSchaffer4.m
• Quadratic.m, SineEnvelope.m, Sinenvsin.m, TestTubeHolder.m, Trigonometric.m
• Wood.m, WWavy.m, XinSheYajngN1.m, XinSheYajngN2.m, Zettl.m