Extract calls to bc* and gmp_* functions to adapter classes
CS fixes
BC break - Remove all static methods on interfaces and matching implementations
Port all remaining tests to PHPUnit
Fix incorrect curve in Secg factory
Pass all tests and remove unused functions/classes
Revert Travis settings
Scrutinizer Auto-Fixes
Extend model with key generation convenience methods
Use make to run builds
Add extra arithmetic tests
Fix bugs detected by Scrutinizer
Remove testdox test output to prevent build timeouts
Scrutinizer Auto-Fixes

This patch was automatically generated as part of the following inspection:
https://scrutinizer-ci.com/g/aztech-digital/php-ecc/inspections/cba2842c-b758-4551-95d9-66e701adc01a

Enabled analysis tools:
 - PHP Analyzer
 - PHP Copy/Paste Detector
 - PHP PDepend
 - PHP Change Tracking Analyzer
Minor fixes

- Use explicit null checks
- Throw \RuntimeException instead of \BadMethodCallExcepion in EcDH
- Fix bug where generated private key secrets could be 0
- Add (some) doc comments
Explicit null check
Update README.md

- Update Contributing instructions
- Add small usage sample
Doc war effort & rename some convenience methods on PubKeys
Minor bugfixes & more doc
More doc fixing