https proxy support

[ashichau]

Description

Adds https_proxy and https_proxy_port parsing to Oracle Net connect descriptors and EZConnect strings.
Preserves proxy settings when connection addresses are generated or reordered.
Adds proxy settings to the transport address and test configuration.
For TCPS connections, the driver:Opens a TCP connection to the proxy.
Sends an HTTP CONNECT host:port request.
Requires a successful 2xx proxy response.
Reuses the same connection for the TCPS/TLS handshake with the database.

Defaults the proxy port to 80 when it is not specified.
Rejects HTTPS proxy usage with non-TCPS connections.

Fixes # (issue)
Https proxy support
#93

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce them. Please also list any relevant details for your test configuration.

• Test A
• Test B

Test Configuration:

• Firmware version:
• Hardware:
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• SDK:

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules