HHH-8302 - add unit test
HHH-8302 init c3p0 initialPoolSize with minPoolSize

Adding C3P0_STYLE_INITIAL_POOL_SIZE directly to c3props doesn't work
because of prefix "c3p0."
Using setOverwriteProperty checks for the nullability of the value and
removes this prefix

Conflicts:
	hibernate-c3p0/src/main/java/org/hibernate/c3p0/internal/C3P0ConnectionProvider.java
HHH-3078 Fixed bug with multiple classloaders and proxy class
HHH-3078 copyright and refactored package