Bug fixes, improvements, and better documentation!

• Fixed pretty_print URL parameter bug that disabled users from turning pretty print off if api.php page had it set to default on using API::set_pretty_print().
• pretty_print only works on version 5.4.0 and up. Prior versions of PHP do not allow use of the JSON_PRETTY_PRINT constant and was causing an error.
• Changed header on pages to output application/json instead of text/javascript
• Added documentation for how to insert/update using the static Database class in README
• Database::execute_from_assoc() now takes only 3 parameters as of commit 83e52cf4
• API::__construct() now dies throwing config_error if database connection is not made
• Added examples/ folder with two example files. More to come!
• Minor improvements to README
• Added changelog file

API Builder PHP Mini Library

Hello world! This is the beta release of the API Builder mini lib. As such, there may be some bugs that you find when using it. I am continuing to develop the project and hope to have more examples and better error handling soon. I would love to hear any bugs, or suggestions, or things you find working well with it.