Extend plist support with raw text or variables

hi @mlynch thx for this #52 ❤️

so i'm suggest add support use plist inlined source from variables:

for example we has:

GOOGLE_SERVICE_PLIST_RAW="<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>CLIENT_ID</key> <string>3853.apps.googleusercontent.com</string> <key>REVERSED_CLIENT_ID</key> <string>com.googleusercontent.apps.38275659253</string> <key>API_KEY</key> <string>AIzaSyDAxktyU</string> <key>GCM_SENDER_ID</key> <string>3592535</string> <key>PLIST_VERSION</key> <string>1</string> <key>BUNDLE_ID</key> <string>com.app.app</string> <key>PROJECT_ID</key> <string>nomad-dev-01</string> <key>STORAGE_BUCKET</key> <string>dev.appspot.com</string> <key>IS_ADS_ENABLED</key> <false/> <key>IS_ANALYTICS_ENABLED</key> <false/> <key>IS_APPINVITE_ENABLED</key> <true/> <key>IS_GCM_ENABLED</key> <true/> <key>IS_SIGNIN_ENABLED</key> <true/> <key>GOOGLE_APP_ID</key> <string>1:\4efc2d2</string> </dict> </plist>"

vars: 
  GOOGLE_SERVICE_PLIST_RAW:

plist:
          - replace: true
            file: GoogleService-Info.plist
            raw:  $GOOGLE_SERVICE_PLIST_RAW

add switch/case raw and write variable value in:

trapeze/packages/configure/src/operations/ios/plist.ts

Lines 8 to 10 in c1c7c81

    
           for (const pop of plistOp) { 
        
             if (pop.file) { 
        
               const file = await ctx.project.ios?.getPlistFile(pop.file);

Is there a reason you need to fill the GoogleService-Info.plist from a variable instead of using the copy operation to add the file?
We had the same issue with that file and I described my workarounds at the time in #94, but now that the copy operation is available, we just use the variables to inject paths to different GoogleService-Info.plist files for different environments and just copy the correct file.

@Crylion

we exclude additional writing of scripts sh
exclude file hits for different environments [production, staging, development]
the file is not stored in git
all secret data is further stored in aws kms

Ended up landing some support for this and will be in the next release after the holidays. Cheers

	for (const pop of plistOp) {
	if (pop.file) {
	const file = await ctx.project.ios?.getPlistFile(pop.file);