Code quality improvements, bugfixes and beginning preparations for 2.0

• Set DefaultMetadataReader when ext-exif is not present #841 (cedricziel)
• Updating twig call to utilise asset(), to match README.md (closes #830) #836 (antoligy)
• Exclude "Tests" directory from classmap #835 (pamil)
• Require components that no longer ship with Symfony FrameworkBundle 3.2 #832 (rpkamp)
• Document how web paths are built #829 (greg0ire)
• Wrap relative path with asset() Twig function #825 (bocharsky-bw)
• Update data-loaders.rst #821 (IllesAprod)
• Updating 2.0 with corrections from 1.0 #820 (antoligy)
• Typo fix #819 (redjanym)
• Fix RST indentation error in AWS S3 cache resolver documentation #809 (GeoffreyHervet)
• Update basic-usage.rst #805 (you-ser)
• Add data_loader config to doc #803 (davidfuhr)
• RST Typo Fix and Clarification for Watermark Docs #802 (robfrawley)
• Update Source to Newly Merged Style Rule Additions #800 (robfrawley)
• Bugfix: Remove Short Array Syntax and Fix (Minor) Recent Merge Issues #799 (robfrawley)
• Add Symfony Framework 3.1.x and 3.2-dev to build matrix #796 (cedricziel)
• Add visibility argument to service definition #795 (cedricziel)
• Bugfix for Failing Tests Introduced in #777 #793 (robfrawley)
• Added php_cs.dist / Updated .styleci.yml / Fixed and updated .travis.yml #792 (robfrawley)
• Add LICENSE.md #790 (robfrawley)
• Updated README.md and RST Documentation #789 (robfrawley)
• Updated CHANGELOG.md #788 (robfrawley)
• List deprecation - closes #731 #787 (antoligy)
• Cleanup FileSystemLoader (Followup to #775) #785 (robfrawley)
• Tempdir for postprocessors #779 (jehaby)
• Add visibility argument to flysystem resolver #777 (cedricziel)
• Amend path resolution handlers and outside root check conditional in FileSystemLoader #775 (robfrawley)
• Scale filter and Downscale and Upscale as derivatives, with a new feature #773 (deviprsd21)
• Applied fixes from StyleCI #768 (lsmith77)
• Replaced deprecated factory_class and factory_method #767 (rvanlaarhoven)
• Update basic-usage.rst #766 (nochecksum)
• Implemented ConfigurablePostProcessorInterface in OptiPngPostProcessor #764 (jehaby)

various bug fixes, added Flysystem resolver and various other feature additions

Note this release requires a higher minimal version of the imagine library "imagine/Imagine": "^0.6.3,<0.7",

• Fix tempnam usages #723
• Quote strings starting '%' in YAML #745
• Add Flysystem resolver #715
• background filter: allow image positioning #721
• Implement Imagine Grayscale filter #638
• Downscale filter scales an image to fit bounding box #696
• Ignore invalid exif orientations #751
• Add configuration options for jpegoptim post-processor
• Enable configuration of post processors using parameters #720 / #756 / #759

Release 1.5.3

• Introduce mozjpeg and pngquant post-processors, add transform options.

Release 1.5.2

• Fix regression in background filter.

Release 1.5.1

• Contains regression fix

Release 1.5.0

• Added ability to process large files stored locally.

Release 1.4.3

• Flysystem loader support added.

Release 1.4.2

• Improve ProxyResolver. Add support of find&replace and regexp strategies.

Release 1.4.1

• Add support of AWS S3 SDK v3.

Release 1.4.0

• Add ability to force resolver