Escape schema name when setting search_path

(cherry picked from commit e708385916ac63e54c5c4d6f78986eb6bf9ebb08)
Add tests for schema name containing special characters

(cherry picked from commit 169c6dfe48e07234f9d083ae92697298e8d5b630)

Conflicts:
	org/postgresql/test/jdbc4/jdbc41/SchemaTest.java
Setting the search_path from currentSchema property is done in startup packet (v3 protocol only)

(cherry picked from commit 3c676cdc5bed5dbd85158628be60bb3261c6e76f)

Conflicts:
	org/postgresql/core/v3/ConnectionFactoryImpl.java
Unescape/unquote result of getSchema

(cherry picked from commit f97294a37e19ab1776ac60768ba335950c0fcaad)

Conflicts:
	org/postgresql/jdbc4/AbstractJdbc4Connection.java
Add a TestSuite for JDBC 4.1

(some changes picked from 420f5eeba07a2e8de7b0b5bb145210be688a04f1)
Merge pull request #232 from alexismeneses/REL9_3_SchemaBackPatch

[backpatch] Fixes on get/set/current-schema (9.3 branch)