[WiP] Add options to manipulate style

[gabriel-samfira]

Two new options were added:

• UseFlowStyle - Will output the entire yaml using Flow style instead of block
• UseSequenceFlowStyle - Will output only sequences using the Flow style

Example:

PS /> $TestYaml = 'networkMapping: {"test_net_1": {"external": true}, "test_net_2": {"external": true}, "test_net_3": {"external": true}, "aNull": null}'
PS /> $x = ConvertFrom-Yaml $TestYaml                                                                                                                    
PS /> ConvertTo-Yaml -Options UseFlowStyle $x
{networkMapping: {test_net_1: {external: true}, test_net_2: {external: true}, aNull: "", test_net_3: {external: true}}}

# Chain more options like OmitNullValues if needed
PS /> ConvertTo-Yaml -Options UseFlowStyle,OmitNullValues $x
{networkMapping: {test_net_1: {external: true}, test_net_2: {external: true}, test_net_3: {external: true}}}

To only output sequences as Flow:

PS /> $testYaml = 'testing: {"aMapping": "test", "aSequence":[1,2,3,4]}'
PS /> $x = ConvertFrom-Yaml $TestYaml                                   
PS /> ConvertTo-Yaml -Options UseSequenceFlowStyle $x
testing:
  aSequence: [1, 2, 3, 4]
  aMapping: test

Fixes: #147

[gabriel-samfira]

CC @RokeJulianLockhart