pam_env: Equal sign not properly handled in conf file

[guidovilla]

If in conf file I write:

variable

or

variable DEFAULT=

the expected behaviour is to remove that variable from the environment. But the parser does not check for '=' signs, so if have this in the conf file (NOT in the env file):

this_does_not_do_what_expected=yeah

or even this:

neither_does_this=ohyeah! DEFAULT=

the module tries to remove the variable "this_does_not_do_what_expected=yeah" from the environment (as per debug log: remove variable "this_does_not_do_what_expected=yeah"), but this results in adding the variable "this_does_not_do_what_expected" instead, with value = "yeah".

Note that this is the reason why the parsing of the user environment file seems to work (see #6)

[t8m]

I believe we should make this behavior official and documented. Of course the attempt to remove the "this_does_not_do_what_expected=yeah" should be dropped too.