E11 V2.0 release notes

Important differences between V1.1 and V2.0 of Ersatz-11:

1. The default amount of memory allocated to the emulated PDP-11 has been
   raised from 248 KB to 384 KB.  This, plus the growth of E11 itself, is
   likely to cause "?Insufficient memory" errors on systems that have a
   significant amount of memory used by TSRs or device handlers.  The PDP-11
   memory allocation may be reduced to fix this, by using the "/MEMORY:n"
   switch on the DOS command line that starts E11, e.g. "E11/MEM:248" will
   restore the V1.1 memory size.

2. DX: and DY: are no longer synonyms.  DX: refers specifically to an RX11
   controller, DY: refers to an RX211.  The SET FLOPPY RX11/RX211 command
   has been removed.

3. The disk controllers are no longer created by default at startup, they
   get created when the first drive is mounted on them and destroyed when
   the last drive is dismounted.

4. The HD: device has changed.  As a result the old HD.SYS and HDX.SYS drivers
   (included with E11 V1.1) no longer work, you should use the ones included
   with E11 V2.0 instead.

5. Bug:  the SET CPU 44 command fails to enable the "MSER" CPU feature, this
   will be fixed in future versions but meanwhile you should use "SET CPU 44
   MSER" to set up an emulated PDP-11/44 CPU.
