Rename module to 'SwiftProtobuf'

It turns out there are other 'Protobuf' modules in
the world.  Since we're already calling this the
"Swift Protobuf" project, we may as well use that
name throughout.

Apologies for the disruption.

Author: tbkka

Makefile

@@ -66,7 +66,7 @@ all: build
 # This also rebuilds LinuxMain.swift to include all of the test cases
 # (The awk script is very fast, so re-running it on every build is reasonable.)
 build:
-	${AWK} -f CollectTests.awk Tests/ProtobufTests/Test_*.swift > Tests/LinuxMain.swift
+	${AWK} -f CollectTests.awk Tests/SwiftProtobufTests/Test_*.swift > Tests/LinuxMain.swift
 	${SWIFT} build
 
 check test: build
@@ -91,8 +91,8 @@ regenerate: regenerate-library-protos regenerate-test-protos
 regenerate-library-protos:
 	for t in ${GOOGLE_LIBRARY_PROTOS}; do \
 		echo google/protobuf/$$t.proto; \
-		${PROTOC} --swift_out=Sources/Protobuf -I Protos Protos/google/protobuf/$$t.proto; \
-		sed -i~ -e 's/^import Protobuf$$//' Sources/Protobuf/$$t.pb.swift; \
+		${PROTOC} --swift_out=Sources/SwiftProtobuf -I Protos Protos/google/protobuf/$$t.proto; \
+		sed -i~ -e 's/^import SwiftProtobuf$$//' -e 's/^import Protobuf$$//' Sources/SwiftProtobuf/$$t.pb.swift; \
 	done
 
 # Rebuild just the protos used by the test suite
@@ -102,14 +102,14 @@ regenerate-test-protos: regenerate-test-protos-google regenerate-test-protos-loc
 regenerate-test-protos-google:
 	for t in ${GOOGLE_TEST_PROTOS}; do \
 		echo google/protobuf/$$t.proto; \
-		${PROTOC} --swift_out=Tests/ProtobufTests -I Protos Protos/google/protobuf/$$t.proto; \
+		${PROTOC} --swift_out=Tests/SwiftProtobufTests -I Protos Protos/google/protobuf/$$t.proto; \
 	done; \
 	echo conformance/conformance.proto; \
-	${PROTOC} --swift_out=Tests/ProtobufTests -I Protos/conformance -I Protos Protos/conformance/conformance.proto; \
+	${PROTOC} --swift_out=Tests/SwiftProtobufTests -I Protos/conformance -I Protos Protos/conformance/conformance.proto; \
 
 # Rebuild just the protos used by the test suite that come from local sources
 regenerate-test-protos-local:
 	for t in Protos/*.proto; do \
 		echo $$t; \
-		${PROTOC} --swift_out=Tests/ProtobufTests -IProtos $$t; \
+		${PROTOC} --swift_out=Tests/SwiftProtobufTests -IProtos $$t; \
 	done