Implement fullGetEnv function

[michalbiesek]

• as a wrapper to call g_fn.getenv and a manual parsing of environ
• when scoping bash calling getenv("SCOPE_CONF_PATH") will return NULL

Ref: #401

Fixes: #1502

[iapaddler]

can we please use braces here for the if and for statements here?

[michalbiesek]

Done

[iapaddler]

if we are using a fullGetEnv() then checkEnv() in utils.c should be using that, it seems?
there are numerous instances where getenv() is called directly. do those need to change?
checkEnv() is called in the constructor before initFn() is called to build the g_fn object.

for verification: ld.so must be resolving getenv() to bash:getenv() else fullSetEnv() would not be required for cfgPath(). accurate?

[michalbiesek]

My focus was to support the init problem - but You are right regarding above especially the part initFn and checkEnv - let's discuss it.

[iapaddler]

assuming that the manual check of environ works, i haven't looked or tested yet, why use g_fn.getenv? is it needed?

on the other side of the same question; there is only place where a manual check of environ could be needed. let's not use it unless it's absolutely needed.

[michalbiesek]

My intentions are following:

• I want to use g_fn.getenv() as first priority since this exact implementation of getenv function used by the application.
• Manual check of environment is the implementation taken from our internal library. I treated this as last resort in case we did not able to resolve the g_fn.getenv function.

[michalbiesek]

My init intentions after the discussion:

• provide comment about the source of implementaiton fallback implementaiton of fullGetEnv
• use fullGetEnv in every valid place in our code
• get rid off g_fn.getenv and depend only on environ parsing directly - the fallback implementaiton

[seanvaleo]

LGTM