el-get-describe: Add punctuation after installation method.

* el-get-list-packages.el (el-get-describe-1): Add punctuation after
  installation method.

Signed-off-by: Rüdiger Sonderfeld <ruediger@c-plusplus.de>
el-get-describe: Inform user about minimum version requirement.

* el-get-list-packages.el (el-get-describe-1): Inform user about
  minimum version requirement.

Signed-off-by: Rüdiger Sonderfeld <ruediger@c-plusplus.de>
Merge pull request #1307 from ruediger/describe-minimum

Describe: minimum Emacs version