Build under Android NDK plus other minor changes

[kmorrissey-mersive]

This pull request has the following changes:

• Provide std functions that are missing under Android NDK so that it builds
• Allow EWS_TEST_DOMAIN environment variable to be undefined under Windows because Windows does not allow environment variable with empty values but it is legitimate for the domain value to be empty (null)
• Allow EWS servers that have self-signed SSL certificates
• Fix incompatibility between Windows and other platforms about min()/max() functions/macros
• Minor changes to constructors based on warnings from CppCheck tool about uninitialized members
• Other changes pulled from otris/master, accidentally without rebasing

[bkircher]

Closed without merging. Branch does not apply cleanly and contains definitions in std namespace. Anyways, Android still on the wish list; #57.