added SentryOptions.enableStartupProfiling

added startupProfilingConfigFile deletion and creation on init
added sampling decision on SDK init with isForNextStartup flag set to true
added SentryOptions.getCacheDirPathWithoutDsn for startupProfiling config file

…to feat/startup-profiling2-add-options

# Conflicts:
#	sentry/src/main/java/io/sentry/SentryOptions.java
#	sentry/src/test/java/io/sentry/SentryOptionsTest.kt
#	sentry/src/test/java/io/sentry/SentryTest.kt

used FileOutputStream instead for FileWriter

* first activity transaction now inherits startup sampling decision, if available
* if a startup profiler was instantiated, it will be reused in AndroidOptionsInitializer, instead of creating a new one
* added ITransactionProfiler.isRunning
* startup profiler and sampling decision is stored in AppStartMetrics
* startup profile is bound to the startup transaction
* added io.sentry.profiling.enable-startup manifest option
* moved profilingTracesHz from SentryAndroidOptions to SentryOptions
* added startup profiling launch in SentryPerformanceProvider
* added isStartupTransaction to TransactionOptions