Update VectorClass to 1.22 release

Changes since 1.19 release are :

2015-05-03 version 1.22

• added optional namespace
• fixed problem with decimal.h

2015-04-24 version 1.21

• fix problems with XOP option in gcc
• improved horizontal_and/or for sse2
• improved Vec2q and Vec4q constructor on Microsoft Visual Studio 2015
• removed warnings by gcc option -Wcast-qual

2015-12-04 version 1.20

• round functions: suppress precision exception under SSE4.1 and higher
• fix compiler problems with AVX512 multiplication in gcc version 5.1
• fix compiler problems with pow function in Microsoft Visual Studio 2015