Workaround for broken SPKAC generated by Chrome

* Valid SPKAC asn1parse:

    0:d=0  hl=4 l= 585 cons: SEQUENCE
    4:d=1  hl=4 l= 305 cons:  SEQUENCE
    8:d=2  hl=4 l= 290 cons:   SEQUENCE
   12:d=3  hl=2 l=  13 cons:    SEQUENCE
   14:d=4  hl=2 l=   9 prim:     OBJECT            :rsaEncryption
   25:d=4  hl=2 l=   0 prim:     NULL
   27:d=3  hl=4 l= 271 prim:    BIT STRING
  302:d=2  hl=2 l=   9 prim:   IA5STRING         :challenge
  313:d=1  hl=2 l=  13 cons:  SEQUENCE
  315:d=2  hl=2 l=   9 prim:   OBJECT            :md5WithRSAEncryption
  326:d=2  hl=2 l=   0 prim:   NULL
  328:d=1  hl=4 l= 257 prim:  BIT STRING

* Offending SPKAC generated by Chrome:

    0:d=0  hl=4 l= 572 cons: SEQUENCE
    4:d=1  hl=4 l= 294 cons:  SEQUENCE
    8:d=2  hl=4 l= 288 cons:   SEQUENCE
   12:d=3  hl=2 l=  11 cons:    SEQUENCE
   14:d=4  hl=2 l=   9 prim:     OBJECT            :rsaEncryption
   25:d=3  hl=4 l= 271 prim:    BIT STRING
  300:d=2  hl=2 l=   0 prim:   IA5STRING         :
  302:d=1  hl=2 l=  11 cons:  SEQUENCE
  304:d=2  hl=2 l=   9 prim:   OBJECT            :md5WithRSAEncryption
  315:d=1  hl=4 l= 257 prim:  BIT STRING
Fix problems with version number format

See github issues 2.
Release preparation
Comment failing doctest with sha512