tools/btatt: Add "read-by-type" command.

Added command for the "Read By Type" request. Sample run:

$ btatt -d 00:02:5B:00:15:10 -v read-by-type 0x0001 0xffff 0x2800
Connecting to device...
att: ATT command 0x08
att: < 08 01 00 ff ff 00 28
att: > 09 04 01 00 00 18 08 00 01 18 09 00 0d 18 11 00 0f 18 15 00 0a 18
Read By Type Response:
	Length: 4
	Attribute Data List:
		Attr Handle: 0x0001, Value: 00 18
		Attr Handle: 0x0008, Value: 01 18
		Attr Handle: 0x0009, Value: 0d 18
		Attr Handle: 0x0011, Value: 0f 18
		Attr Handle: 0x0015, Value: 0a 18
src/shared/att: Add "Read" request and response.

This patch adds support for the "Read" request and response with their
corresponding parameter structures.
unit/test-att: Add unit test for "Read" request/response.

Added test cases for the "Read" request/response.
tools/btatt: Add "read" command.

Added command for the "Read" request. Sample run:

$btatt -d 00:02:5B:00:15:10 -v read 0x0009
Connecting to device...
att: ATT command 0x0a
att: < 0a 09 00
att: > 0b 0d 18
Read response:
	Value: 0d 18
src/shared/att: Add "Read Blob" request and response.

This patch adds support for the "Read Blob" request and response with
their corresponding parameter structures.
unit/test-att: Add unit test for "Read Blob" request/response.

Added test cases for the "Read Blob" request/response.
tools/btatt: Add "read-blob" command.

Added command for the "Read Blob" request. Sample run:

$btatt -d 00:02:5B:00:15:10 -v read-blob 0x0002 3
Connecting to device...
att: ATT command 0x0c
att: < 0c 02 00 03 00
att: > 0d 00 2a
Read Blob response:
	Part Value: 00 2a

$btatt -d 00:02:5B:00:15:10 -v read-blob 0x0002 5
Connecting to device...
att: ATT command 0x0c
att: < 0c 02 00 03 00
att: > 0d
Read Blob response:
	Part Value: 0 bytes
src/shared/att: Add "Read Multiple" request and response.

This patch adds support for the "Read Multiple" request and response
with their corresponding paramter structures.
unit/test-att: Add unit test for "Read Multiple" request/response.

Added test cases for the "Read Multiple" request/response.
tools/btatt: Add "read-multiple" command.

Added command for the "Read Multiple" request.
src/shared/att: Add "Read By Group Type" request and response.

This patch adds support for the "Read By Group Type" request and
response with their corresponding parameter structures.
unit/test-att: Add unit test for "Read By Group Type" request/response.

Added test cases for the "Read By Group Type" request/response.
tools/btatt: Add "read-by-group-type" command.

Added command for the "Read By Group Type" request. Sample run:

$btatt -d 00:02:5B:00:15:10 -v read-by-group-type 0x0001 0xffff 0x2800
Connecting to device...
att: ATT command 0x10
att: < 10 01 00 ff ff 00 28
att: > 11 06 01 00 07 00 00 18 08 00 08 00 01 18 09 00 10 00 0d 18
Read By Group Type response:
	Length: 6
	Attribute Data List:
		Attr Handle: 0x0001, End Grp Handle: 0x0007, Value: 00 18
		Attr Handle: 0x0008, End Grp Handle: 0x0008, Value: 01 18
		Attr Handle: 0x0009, End Grp Handle: 0x0010, Value: 0d 18
src/shared/att: Add "Write" request and response.

This patch adds support for the "Write" request and response with the
parameters structure for the request.
unit/test-att: Add unit test for "Write" request/response.

Added test cases for the "Write" request/response.
tools/btatt: Add "write" command.

Added command for the "Write" request. Sample run:

$btatt 00:02:5B:00:15:10 -v write 0x000c 01 00
Connecting to device...
att: ATT command 0x12
att: < 12 0c 00 01 00
att: > 1b 0b 00 16 6c fb 01
att: > 13
Write response: OK

$btatt 00:02:5B:00:15:10 -v write 0x000c 00 00
Connecting to device...
att: ATT command 0x12
att: < 12 0c 00 01 00
att: > 13
Write response: OK