CONFIG: bump API version number to 1901 to register recent changes

  - objectRegistry search, erase methods
  - clip, minMax
  - function object triggering
  ...

META-INFO/api-info

-api=1812
-patch=190129
+api=1901
+patch=0

wmake/rules/General/general

 #-------------------------------*- makefile -*---------------------------------
-WM_VERSION = OPENFOAM=1812
+WM_VERSION = OPENFOAM=1901
 
 AR         = ar
 ARFLAGS    = cr