Support curl as alternative to wget
Check existence of required files (fixes #6), include error text on failure output

- Check existence of required Certificate/Key files before doing anything (fixes #6)
- On faults, include the more detailed text in output to help debugging
- Check for intermediate files during the post processing to abort early/more cleanly
Move all User "serviceable" settings to the top, set connect-timeout for curl as well
Fix company name
Merge pull request #5 from ickiller/master

Support for curl as alternative to wget, various other improvements