Remove env hostname replacement

[tosih]

Remove env hostname replacement as we have alias support. Also, the existing regex was not compatible with env vars with . in them: i.e. http.host=1.2.3.4

[thejsj]

Beautiful. LGTM. Presupposing all tests pass.

[anandkumarpatel]

http.host=1.2.3.4 is not a valid env

[tosih]

I agree, Anand. IEEE

These strings have the form name=value; names shall not contain the character '='. For values to be portable across systems conforming to IEEE Std 1003.1-2001, the value shall be composed of characters from the portable character set (except NUL and as indicated below).
...
Environment variable names used by the utilities in the Shell and Utilities volume of IEEE Std 1003.1-2001 consist solely of uppercase letters, digits, and the '_' (underscore) from the characters defined in Portable Character Set and do not begin with a digit. Other characters may be permitted by an implementation; applications shall tolerate the presence of such names.
So while the names may be valid, your shell might not support anything besides letters, numbers, and underscores.

Unfortunately, some containers use env variables in that fashion, such as ElasticSearch.