PhpExecutableFinder return false not null.

reference #16
Find the executables rigth after setting the configuration.

reference #16
Fix typo in method name.
Lazy create symfttpd in the application.
Allow using in project when installed by composer
Merge pull request #19 from marekkalnik/2.0.0

Allow using in project when installed by composer
Update documentation

reference #7
[README] Change spawn command
Merge pull request #20 from alixc/2.0.0

[README] Change spawn command
Update dependencies
Close #21
Skipped tests for a moment
Update vendors
Inject symfttpd in Application and in the added Command
Split SymfttpdConfiguration in two parts
Remove validator, configurator and mksymlink
Add factory class.
Add Configuration definition class
Add SymfttpdFile to handle the configuration file loading
Add Config