Added functionality to ignore .env # comments, trim EOL whitespace, detect different EOL terminators

[seanblonien]

• Valid .env file comments that start with #, so added functionality to ignore anything after that symbol
  • Apparently dontenv doesn't even have this feature, but I figured couldn't hurt
• Also trimmed whitespace at end of line
• Changed it to auto-detect the EOL and split the string accordingly (allowing for \r\n and \n line endings)

[kHRISl33t]

Nice touch to the package, good work, thank you! :)
One small comment about the style, otherwise it looks good.

[seanblonien]

If someone needs an environment variable value with a "#" in it, this solution doesn't really allow for that, but I think that's fine and not a common use-case, and easily solvable by replacing a pre-defined character pattern (such as HASH and doing a window.__RUNTIME_CONFIG__.variableName.replace(/HASH/g, '#') ) if someone truly needs that functionality

[seanblonien]

@kHRISl33t any more feedback on this?

[kHRISl33t]

@seanblonien will merge it later today (in a few hours), I just need to finish the docs for it :)
Sorry, I have been swamped with work in the last few days.