Syntax Error when deploying iApp template using iControl ReST API

After much experimentation, I got it working. For anyone else who may find this useful:

This is the original TMSH method of creating an iApp template:

create test_template {
actions replace-all-with {
definition {
html-help {

}
implementation {
tmsh::create {
ltm node 10.111.222.102
address 10.111.222.102
}
tmsh::create {
ltm node 10.111.222.103
address 10.111.222.103
}

tmsh::create {
ltm pool iApp-Automation-Test-ebiz-http
members replace-all-with {
10.111.222.102:80 {
address 10.111.222.102
}
10.111.222.103:80 {
address 10.111.222.103
}
}
monitor http 
}

}
macro {
}
presentation {
 insert apl script
}
}
}
description none
requires-bigip-version-max none
requires-bigip-version-min none
requires-modules none
}

To convert the TMSH template code to ReST client (ARC or POSTMAN) syntax, you must replace all the line breaks with \n. In our case it would look like this:

Method: POST
URL: https://ltmip/mgmt/tm/sys/application/template/
Body: {"name":"test_template","actions":[{"name":"definition","htmlHelp":"","implementation":"tmsh::create { \n ltm node 10.111.222.102 \n address 10.111.222.102 \n } \n tmsh::create { \n ltm node 10.111.222.103 \n address 10.111.222.103 \n } \n  \n tmsh::create { \n ltm pool iApp-Automation-Test-ebiz-http \n members replace-all-with { \n 10.111.222.102:80 { \n address 10.111.222.102 \n } \n 10.111.222.103:80 { \n address 10.111.222.103 \n } \n } \n monitor http  \n }","macro":"","roleAcl":["admin","manager","resource-admin"],"presentation":""}],"totalSigningStatus":"not-all-signed","requiresBigipVersionMax":"","ignoreVerification":"false","requiresModules":[""],"requiresBigipVersionMin":"11.0.0"}

To convert to CURL, the additional step of escaping all the quotation marks must be taken:

curl -sku admin:admin -X POST -H "Content-type: application/json" -d "{\"name\":\"test_template\",\"actions\":[{\"name\":\"definition\",\"htmlHelp\":\"\",\"implementation\":\"tmsh::create { \n ltm node 10.111.222.102 \n address 10.111.222.102 \n } \n tmsh::create { \n ltm node 10.111.222.103 \n address 10.111.222.103 \n } \n  \n tmsh::create { \n ltm pool iApp-Automation-Test-ebiz-http \n members replace-all-with { \n 10.111.222.102:80 { \n address 10.111.222.102 \n } \n 10.111.222.103:80 { \n address 10.111.222.103 \n } \n } \n monitor http  \n }\",\"macro\":\"\",\"roleAcl\":[\"admin\",\"manager\",\"resource-admin\"],\"presentation\":\"\"}],\"totalSigningStatus\":\"not-all-signed\",\"requiresBigipVersionMax\":\"\",\"ignoreVerification\":\"false\",\"requiresModules\":[\"\"],\"requiresBigipVersionMin\":\"11.0.0\"}" https://ltmip/mgmt/tm/sys/application/template

Hope somebody finds this useful.