Add "new-testnet" command to lcli (#853)

* Add new command to lcli

* Add lcli to dockerfile

* Add min validator count param

* Fix bug in arg parsing

* Fix 0x address prefix issue

* Add effective balance increment

* Add ejection balance

* Fix PR comments

lcli/src/helpers.rs

@@ -0,0 +1,85 @@
+use clap::ArgMatches;
+use hex;
+use std::path::PathBuf;
+use std::time::{SystemTime, UNIX_EPOCH};
+use types::Address;
+
+pub fn time_now() -> Result<u64, String> {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .map(|duration| duration.as_secs())
+        .map_err(|e| format!("Unable to get time: {:?}", e))
+}
+
+pub fn parse_path_with_default_in_home_dir(
+    matches: &ArgMatches,
+    name: &'static str,
+    default: PathBuf,
+) -> Result<PathBuf, String> {
+    matches
+        .value_of(name)
+        .map(|dir| {
+            dir.parse::<PathBuf>()
+                .map_err(|e| format!("Unable to parse {}: {}", name, e))
+        })
+        .unwrap_or_else(|| {
+            dirs::home_dir()
+                .map(|home| home.join(default))
+                .ok_or_else(|| format!("Unable to locate home directory. Try specifying {}", name))
+        })
+}
+
+pub fn parse_u64(matches: &ArgMatches, name: &'static str) -> Result<u64, String> {
+    matches
+        .value_of(name)
+        .ok_or_else(|| format!("{} not specified", name))?
+        .parse::<u64>()
+        .map_err(|e| format!("Unable to parse {}: {}", name, e))
+}
+
+pub fn parse_u64_opt(matches: &ArgMatches, name: &'static str) -> Result<Option<u64>, String> {
+    matches
+        .value_of(name)
+        .map(|val| {
+            val.parse::<u64>()
+                .map_err(|e| format!("Unable to parse {}: {}", name, e))
+        })
+        .transpose()
+}
+
+pub fn parse_address(matches: &ArgMatches, name: &'static str) -> Result<Address, String> {
+    matches
+        .value_of(name)
+        .ok_or_else(|| format!("{} not specified", name))
+        .and_then(|val| {
+            if val.starts_with("0x") {
+                val[2..]
+                    .parse()
+                    .map_err(|e| format!("Unable to parse {}: {:?}", name, e))
+            } else {
+                Err(format!("Unable to parse {}, must have 0x prefix", name))
+            }
+        })
+}
+
+pub fn parse_fork_opt(matches: &ArgMatches, name: &'static str) -> Result<Option<[u8; 4]>, String> {
+    matches
+        .value_of(name)
+        .map(|val| {
+            if val.starts_with("0x") {
+                let vec = hex::decode(&val[2..])
+                    .map_err(|e| format!("Unable to parse {} as hex: {:?}", name, e))?;
+
+                if vec.len() != 4 {
+                    Err(format!("{} must be exactly 4 bytes", name))
+                } else {
+                    let mut arr = [0; 4];
+                    arr.copy_from_slice(&vec);
+                    Ok(arr)
+                }
+            } else {
+                Err(format!("Unable to parse {}, must have 0x prefix", name))
+            }
+        })
+        .transpose()
+}