Adding custom envelope key option for server and client header fix (take 2 for 1208 and 1170)

[smokhov]

• Closes Adding custom envelope key option for server #1208
• Closes soap-header-fix #1170
• Hopefully helps Add custom name spaces while defining args body #1292

This PR supersedes #1208 (by @gamzeoguz) by making sure the tests pass, adding 2 new tests and covering Faults. The original PR's 2 tests were not passing because actually they were Faults in response as empty Body is not allowed at the server by default here:

node-soap/src/server.ts

Line 322 in 9452702

if (!body) {

Thus. it was failing to parse. I've converted those to Fault tests instead with and without envelopeKey set to soapenv. To cover happy-case scenarios I've added two more tests with some actual Body and expected response from other tests, with and without envelopeKey set to soapenv at for the client with some request data. So this covers #1208.

For #1170 (by @amalashenok) at first I though it was also relevant as the line was around the envelopeKey handling for the client, but it turns out it was not the case, so I wrote a brand new test for it after reproduction. Please check.

[smokhov]

Current coverage:

File	% Stmts	% Branch	% Funcs	% Lines	Uncovered Line #s
All files	94.3	90.77	92.26	94.4
node-soap	100	100	100	100
index.js	100	100	100	100
node-soap/src	92.8	85.99	91.15	92.74
client.ts	92.05	87.01	83.72	92.3	...,423,454,496-500,569-572
http.ts	92.17	83.87	100	92.17	145-148,195-201,227,231,236
nscontext.ts	86.36	82.5	100	86.36	...,51-57,84-86,138,161,229
server.ts	92.43	85.98	100	92.36	...,437,473,517,523,548-558
soap.ts	97.53	91.3	76	97.01	45-46
utils.ts	100	85.71	100	100	10-12
node-soap/src/security	96.42	96.21	88.67	96.97
BasicAuthSecurity.ts	88.88	50	75	88.88	22
BearerSecurity.ts	87.5	100	75	87.5	20
ClientSSLSecurity.ts	100	100	100	100
ClientSSLSecurityPFX.ts	100	100	100	100
NTLMSecurity.ts	88.88	100	75	88.88	29
WSSecurity.ts	97.61	94.44	100	97.61	103
WSSecurityCert.ts	98.9	97.36	93.75	100	125
WSSecurityCertWithToken.ts	100	96	100	100	105
WSSecurityPlusCert.ts	14.28	100	0	16.66	6-13
index.ts	100	100	100	100
node-soap/src/wsdl	94.8	92.6	95.12	94.92
elements.ts	97.84	96.62	97.29	98	...-414,431,567,581,629,923
index.ts	92.55	90.58	91.83	92.66	...1391-1392,1427-1430,1435

[smokhov]

Did a final test for #1170 so over to you @w666