Fix slow fork bomb when directory containing getssl isn't writeable (…).  
_Note failed tests are just due to slow DNS propagation_

Change to use -sigalgs.  Fixes #570

getssl updets itself by:
- checking for a new version
- if so:
  - download the new one into a tmp location
  - rename the current one to name with version appended
  - rename the tmp file to the current location
  - run the new version
If the renaming fails, the old version gets run, which again downloads, etc.
Now exit if the rename (install command) fails.

Support space delimited SANS

Remove manual ACMEv1 -> ACMEv2 upgrade information

Fix CHECK_REMOTE for DUAL_RSA_ECDSA

.gitattributes added

Fix revoke when no CA suffix is specified

Fixes --revoke (#558)
Adds --notify-valid (#559)

Auto upgrade CA url to ACMEv02

Add support for custom domain template

Update revision history and version