length zero (to indicate empty string). And a NULL value.

…return shadowing rule + replacement of os.Error by error)

Conflicts:
	handler.go
	mysql_test.go
	packet.go
	result.go

Conflicts:
	convert.go
	error.go
	handler.go
	mysql.go
	mysql_test.go
	packet.go
	result.go
	statement.go

Merged most of the branches which contained actual changes
Ensured syntaxic correctness
Ensured existing tests run
Migrated to new src structure compatible with "go build"
:

fix ColumnValue type usage broken from previous merge in handler.go
fix typo in packet.go
fix readlengthcodedbytes func broken from merge and in packet.go
replace various os.Error with error