Added input option checks and messages
Basic SSL/TLS setup for installer
 - Need to work on cafile downloads as an option where not available at install time
Bundle cacert.pem file within installer for last-resort distribution
 - This is ignored if a system level cert bundle is located or user passes a bundle filepath to installer
Use tmp directory for stashing a copy of bundled cacert.pem
Restore error handler before Exception throw
Merge remote-tracking branch 'padraic/tls-config'
Check for vulnerable php versions before using openssl_x509_parse
Fixed handling of bundled CA file, refs #61