Fix infinite recursion in GetMem

* Remove JclBase.GetMem: gives an infinite recursion error. Also is
unnecessary since fpc is using out now and
Improve package settings

* The package compiles now as needed
* Added missing files
* Removed unnecessary options
* Add more fpc/Lazarus files to gitignore
Improve gitignore to avoid lib diretories

* Add more specific rules in gitignore so all lib files created by
Lazarus are ignored
Add jclfpc.inc

* Added jclfpc.inc. The installation process of a Lazarus package does
not require a install script
Adapt ExprEval example to Lazarus

Make ExprEval example compatible with Lazarus