Use "context" to contain run details (#14)

* Create "context" to contain run details

* Use context in tests and benchmarks

tests/common.rs

@@ -1,18 +1,26 @@
 use clap::{App, Arg};
+use starship::context::Context;
 use starship::modules;
-use std::path::Path;
+use std::path::PathBuf;
 
-pub fn render_segment(module: &str, path: &Path) -> String {
-    render_segment_with_status(module, path, "0")
+pub fn render_segment<T>(module: &str, path: T) -> String
+where
+    T: Into<PathBuf>,
+{
+    render_segment_with_status(module, &path.into(), "0")
 }
 
-pub fn render_segment_with_status(module: &str, path: &Path, status: &str) -> String {
+pub fn render_segment_with_status<T>(module: &str, path: T, status: &str) -> String
+where
+    T: Into<PathBuf>,
+{
     // Create an `Arg` with status_code of "0"
     let args = App::new("starship")
         .arg(Arg::with_name("status_code"))
         .get_matches_from(vec!["starship", status]);
+    let context = Context::new_with_dir(args, path.into());
 
-    let segment = modules::handle(module, path, &args);
+    let segment = modules::handle(module, &context);
 
     segment.unwrap().output()
 }