* reverseproxy: do not parse upstream address too early if it contains replaceble parts
* remove unused method
* cleanup
* accommodate partially replaceable port
* added some tests for parseUpstreamDialAddress
Test 4 fails because it produces "[[::1]]:80" instead of "[::1]:80"
* support absolute windows path in unix reverse proxy address
* make IsUnixNetwork public, support +h2c and reuse it
* add new tests
