add encoding and licence to properties
remove useless pluginManagement section
fix ID when not logged (and javadoc and return null instead of a empty string)
use a String ID or a Date ID. Both are possibles.
upgrade .gitignore
add function to convert ID from Date to String and String to Date
add a function to get the count of links in the all shaarli
use apache 4.3.1 libraries

This reverts commit 8004f1fe6c44a206a08008ce68219ef8027807c3.
update README

Conflicts:

	README.md
classes normalization
add test units
remove proguard obfuscation (not good for an OSS library)
update pom to new parent version and add logging support