add OpenWatcom setup #63

Job	Run time
Prepare-Docs	33s
Build-OpenWatcom19-OS2	44s
Build-Wart	36s
C-Kermit-Linux-Build-Test	1m 13s
Get-CACerts-Bundle	4s
Build-OpenWatcom19-Win32	53s
Build-OpenWatcom19-Win32-NT-legacy	48s
Build-MinGW64-Linux	1m 22s
Build-VCT2003-PSDK2003 (yes)	49s
Build-VCT2003-PSDK2003 (no)	45s
Build-PSDK2003SP1-IA64	1m 0s
Build-PSDK71 (ia64)	1m 8s
Build-VisualCxx (x86, 14.2)	1m 18s
Build-VisualCxx (x86, 14.4)	1m 19s
Build-VisualCxx (x64, 14.2)	1m 20s
Build-VisualCxx (x64, 14.4)	1m 13s
Build-VisualCxx (x64_arm, 14.4)	1m 18s
Build-VisualCxx (x64_arm64, 14.4)	1m 17s
	17m 40s

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