Adds support for variable size numerical container (new IMC type)

[oysstu]

This adds support for the variable sized numerical container type in IMC (pull request).

Changes include

• Serialization
• Deserialization
• JSON output (ex: "vectorint8": [-79, 118, -119, 110, 0, -116, 94, 34, -62])
• IMC definitions generation (std::vector)
• IMC test generation (now also outputs JSON for each message being parsed)

The JSON implementation required some refactoring to avoid changing the behavior for rawdata fields (std::vector), due to the vector template.

Example message

<message id="3000" name="Vector Test" abbrev="VectorTest" source="vehicle">
    <field name="VUInt8" abbrev="VUInt8" type="vector" vector-type="uint8_t"/>
    <field name="VUInt16" abbrev="VUInt16" type="vector" vector-type="uint16_t"/>
    <field name="VUInt32" abbrev="VUInt32" type="vector" vector-type="uint32_t"/>
    <field name="VUInt64" abbrev="VUInt64" type="vector" vector-type="uint64_t"/>
    <field name="VInt8" abbrev="VInt8" type="vector" vector-type="int8_t"/>
    <field name="VInt16" abbrev="VInt16" type="vector" vector-type="int16_t"/>
    <field name="VInt32" abbrev="VInt32" type="vector" vector-type="int32_t"/>
    <field name="VInt64" abbrev="VInt64" type="vector" vector-type="int64_t"/>
    <field name="VFp32" abbrev="VFp32" type="vector" vector-type="fp32_t"/>
    <field name="VFp64" abbrev="VFp64" type="vector" vector-type="fp64_t"/>
</message>

Example JSON output from test_IMC.cpp below

{
  "abbrev": "VectorTest",
  "timestamp": "0.240822519036",
  "src": "13178",
  "src_ent": "146",
  "dst": "47524",
  "dst_ent": "0",
  "vuint8": [221, 156, 136],
  "vuint16": [37448, 57766],
  "vuint32": [],
  "vuint64": [534796193650451416, 13968894843252329076, 12528655269392993852, 1382089629888762297],
  "vint8": [-79, 118, -119, 110, 0, -116, 94, 34, -62],
  "vint16": [13679, -17283, -256, -11933, -16986, -18199, 7330, 15935, -27224],
  "vint32": [1133517027, 1100964103, 622779471, 2130846750, -1860246269, -586430523, -1464696739, 985052755, 1244632231],
  "vint64": [-3698527484349829534, 3759153311435130465, -3979969022960290610, -3921901367132325590, -1239570279959320365, 1434379472680176510, -4609213349486860242],
  "vfp32": [0.773889362812, 0.39666813612, 0.895049273968],
  "vfp64": [0.319782122474, 0.0669650237304, 0.601433012171]
}