Squashed 'src/Core/' content from commit f5a576e

git-subtree-dir: src/Core
git-subtree-split: f5a576e0fe5abe7819e808a5ca6121c368b3a6bf
Merge commit '13014945aca69846c0a63dc62100cc4c7bf12aea' as 'src/Core'
Squashed 'src/System/' content from commit 48c27fe

git-subtree-dir: src/System
git-subtree-split: 48c27fe41ec43c66c997aadee224d28a15b39749
Merge commit '33dc37cc223a39aabcf27268c10bba4ed64337f4' as 'src/System'
Squashed 'src/Front/' content from commit e80d256

git-subtree-dir: src/Front
git-subtree-split: e80d256217cfc50c4a9cd9cbb438cc48d14ae7cd
Merge commit 'ba27af6841127eecde97c23151262493cce416c0' as 'src/Front'
add examples folder and composer.json
Add phpunit.xml and some tests