Handle grep output

- Handle standard filepath:code and filepath:line_number:code output
  as produced by `git grep`, `rg -H`, `grep -H`, etc (with -n for line
  numbers).

- Retain the match highlighting as produced by the grep tool, and
  expose it in delta's color output styled with grep-match-style.
  (Note that --color=always is needed to retain the color if piping
  into delta, but not for `git grep` when delta is configured as git's
  pager)

- Special handling of -p, and -W options of `git grep`: these display
  the function context in which the matches occur.

- `navigate` keybindings jump between match function contexts under
  `git grep -p` and between matching lines under `git grep -W`.

Thanks @zachriggle for the proposal.
Fixes #769

1 files changed, 2 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 9ea4d211..8f1f8602 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -32,6 +32,8 @@ lazy_static = "1.4"
 palette = "0.6.0"
 pathdiff = "0.2.1"
 regex = "1.4.6"
+serde = { version = "1.0.118", features = ["derive"] }
+serde_json = "1.0.70"
 shell-words = "1.0.0"
 smol_str = "0.1.18"
 structopt = "0.3.25"