fix change flag name end_after_checks to continue_after_checks (#1573)

## Issue Addressed

Resolve #1387 

## Proposed Changes

Replace flag name **end_after_checks** to ** continue_after_checks**
Change condition to simple (remove **!**, It's no change logic.)

## Additional Info

Operation check
- [x] subcommand `eth1-sim` with ganach-cli
  - [x] `./simulator eth1-sim` -> test is completes
  - [x] `./simulator eth1-sim --continue_after_checks` -> test is never completes
  - [x] `./simulator eth1-sim -c` -> test is never completes
  - [x] `./simulator eth1-sim -c true` -> error: Found (clap)
  - [x] `./simulator eth1-sim -c false` -> error: Found (clap)
- [x] subcommand `no-eth1-sim`
  - [x] `./simulator no-eth1-sim` -> test is completes
  - [x] `./simulator no-eth1-sim --continue_after_checks` -> test is never completes
  - [x] `./simulator no-eth1-sim -c` -> test is never completes
  - [x] `./simulator no-eth1-sim -c true` -> error: Found (clap)
  - [x] `./simulator no-eth1-sim -c false` -> error: Found (clap)

testing/simulator/src/cli.rs

@@ -36,11 +36,11 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                         .takes_value(true)
                         .default_value("4")
                         .help("Speed up factor"))
-                    .arg(Arg::with_name("end_after_checks")
-                        .short("e")
-                        .long("end_after_checks")
+                    .arg(Arg::with_name("continue_after_checks")
+                        .short("c")
+                        .long("continue_after_checks")
                         .takes_value(false)
-                        .help("End after checks (default true)"))
+                        .help("Continue after checks (default false)"))
         )
         .subcommand(
             SubCommand::with_name("no-eth1-sim")
@@ -64,11 +64,11 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                         .takes_value(true)
                         .default_value("4")
                         .help("Speed up factor"))
-                    .arg(Arg::with_name("end_after_checks")
-                        .short("e")
-                        .long("end_after_checks")
+                    .arg(Arg::with_name("continue_after_checks")
+                        .short("c")
+                        .long("continue_after_checks")
                         .takes_value(false)
-                        .help("End after checks (default true)"))
+                        .help("Continue after checks (default false)"))
         )
         .subcommand(
             SubCommand::with_name("syncing-sim")

testing/simulator/src/eth1_sim.rs

@@ -17,12 +17,12 @@ pub fn run_eth1_sim(matches: &ArgMatches) -> Result<(), String> {
         .expect("missing validators_per_node default");
     let speed_up_factor =
         value_t!(matches, "speed_up_factor", u64).expect("missing speed_up_factor default");
-    let end_after_checks = !matches.is_present("end_after_checks");
+    let continue_after_checks = matches.is_present("continue_after_checks");
 
     println!("Beacon Chain Simulator:");
     println!(" nodes:{}", node_count);
     println!(" validators_per_node:{}", validators_per_node);
-    println!(" end_after_checks:{}", end_after_checks);
+    println!(" continue_after_checks:{}", continue_after_checks);
 
     // Generate the directories and keystores required for the validator clients.
     let validator_files = (0..node_count)
@@ -174,9 +174,9 @@ pub fn run_eth1_sim(matches: &ArgMatches) -> Result<(), String> {
         onboarding?;
 
         // The `final_future` either completes immediately or never completes, depending on the value
-        // of `end_after_checks`.
+        // of `continue_after_checks`.
 
-        if !end_after_checks {
+        if continue_after_checks {
             future::pending::<()>().await;
         }
         /*

testing/simulator/src/no_eth1_sim.rs

@@ -17,12 +17,12 @@ pub fn run_no_eth1_sim(matches: &ArgMatches) -> Result<(), String> {
         .expect("missing validators_per_node default");
     let speed_up_factor =
         value_t!(matches, "speed_up_factor", u64).expect("missing speed_up_factor default");
-    let end_after_checks = !matches.is_present("end_after_checks");
+    let continue_after_checks = matches.is_present("continue_after_checks");
 
     println!("Beacon Chain Simulator:");
     println!(" nodes:{}", node_count);
     println!(" validators_per_node:{}", validators_per_node);
-    println!(" end_after_checks:{}", end_after_checks);
+    println!(" continue_after_checks:{}", continue_after_checks);
 
     // Generate the directories and keystores required for the validator clients.
     let validator_files = (0..node_count)
@@ -141,9 +141,9 @@ pub fn run_no_eth1_sim(matches: &ArgMatches) -> Result<(), String> {
         start_checks?;
 
         // The `final_future` either completes immediately or never completes, depending on the value
-        // of `end_after_checks`.
+        // of `continue_after_checks`.
 
-        if !end_after_checks {
+        if continue_after_checks {
             future::pending::<()>().await;
         }
         /*